Bamboo for Gardens 0881925071, 9780881925074

Citation preview

wherever they are used. Unfortunately, however, they are too often kept out of gardens

for fear of their invasive qualities or lack of hardiness. In truth, these elegant grasses can achieve dramatic yet restrained effects in a

range of climates. Their uses include both the ornamental, offering striking foliage and culms, and the practical, providing screening or erosion control, not to mention the culinary treat of bamboo shoots and the structural

qualities of the culm wood. Tropical and subtropical bamboos present many possibilities for landscapes in warmer climates, while the hardier species can be grown as far north as

Minnesota in the United States and in the coldest areas of England and continental Europe. Bamboo culture has a long and distinguished legacy in East Asia, but much remains to be explored by Western gardeners and landscapers. Bamboo expert and aficionado Ted Jordan Meredith provides a thorough and multifaceted treatment of these ancient grasses, covering origins and history, structure and form, cultivation and propagation, landscaping, and taxonomy and identification.

He offers insight into selecting the right plant for the right situation, and presents useful advice on the best methods for containing potentially invasive forms. The bulk of the book is an encyclopedia

of bamboo genera, species, and cultivars. More than 300 bamboos from 40 genera are described in detail, providing information on size, lighting and temperature requirements,

native range, physical characteristics, and landscape and other uses. Meredith’s excellent color photos and clear line drawings effectively illustrate both the details and

broader effects of these exquisite plants. Whether you are a home gardener or a professional grower, Bamboo for Gardens tells you all you need to know to bring bamboo into your life and landscape.

Digitized by the Internet Archive in 2021 with funding from Kahle/Austin Foundation

https://archive.org/details/bambooforgardensO000mere

Bamboo for Gardens

BAMBOO for Gardens

TED

JORDAN

TIMBER

MEREDITH

PRESS

Portland - Cambridge

Frontispiece: Chusquea culeou ‘Cana Prieta’. Author’s garden.

Copyright © 2001

by Ted Jordan Meredith. All rights reserved.

All photographs and drawings are by Ted Jordan Meredith. Published in 2001 by Timber Press, Inc.

Timber Press

The Haseltine Building

2 Station Road

133 S.W. Second Avenue, Suite 450 Portland, Oregon 97204, U.S.A.

— Swavesey Cambridge CB4 5QJ, U.K.

www.timberpress.com Reprinted 2002, 2003, 2005 Designed by Susan Applegate Printed in Hong Kong

Library of Congress Cataloging-in-Publication Data

Meredith, Ted. Bamboo for gardens/ Ted Jordan Meredith. p. cm.

Includes bibliographical references (p.

).

ISBN 0-88192-507-1

1. Bamboo. I. Title. SB413.B2 M47 2001 635.9'349—dc21 2001035236

Contents

Foreword, 7 Preface, 11 Acknowledgments,

13

Chapter 1. Bamboo and the Grass Family, 17 Origin and Distribution, 20

Woody and Herbaceous Bamboos, 25 Chapter 2. Structure and Function, 27 Segmented

Rhizomes,

Structure, 27

32

Roots, 35 Culms, 36 Branches, 40 Leaves, 42 Flowers and Flowering, 50 Seeds, 59 Rhizome Morphology and Clump Habit, 61 Chapter 3. Culture, 75 Growth, 75 Cultural Requirements, 89 Buying Bamboo, Harvesting,

115

109

Chapter 4. Propagation,

120

Propagating from Seed, 120 Vegetative Propagation,

125

Chapter 5. Landscaping and Maintenance,

149

Controlling Spread, 153 Controlling Height, 162 Thinning and Pruning, Container Bamboos,

165

177

Sizes, Shapes, and Colors, 179 Creating Screens and Hedges,

190

Chapter 6. Bamboo Uses, 195 Bamboo in Traditional Economies, Bamboo in Modern Economies,

195

197

Eating Bamboo, 204 Chapter 7. Bamboo in America, 210 American

Researchers and Proponents,

211

End of an Era, 214 Overcoming an Archaic Law, 215 The American

Bamboo

Society, 216

The Future, 220 Chapter 8. Taxonomy, 222 Evolution of Bamboo Taxonomy, 224 Molecular Techniques and Cladistics, 227 Bamboo Redefined, 229 Identification and Naming, 230 Chapter 9. Bamboo Genera, Species, and Cultivars, 233 Bamboos for Special Situations, 375 Botanical Gardens, 379 Glossary, 380 Bibliography, 387 Index, 399

Foreword

BAMBOO

DOES THINGS no other plant can. In the human landscape, these abil-

ities are unparalleled. A neighbor's house is constructed too close for comfort, and a living, breathing, moving screen of green is desired to ease the claustrophobia. Bamboos meet the challenge, and within a very short period of time, a new environment

is created. Our vision is diverted to the swaying stems, the fluttering

leaves, the nesting birds, and the cool shadows. Relieved, the house next door is forgotten. This is what happened to Ted Jordan Meredith, and we are lucky for it. He was introduced to bamboo in just this way, and his research led not only to his successful planting of a privacy screen, but to this book. On first glance, bamboos come

completely

intriguing,

arouse curiosity, but with further study, they bewith

their myriad

growth habits. The often-misunderstood

shapes

and

sizes, colors,

and

flowering cycles of many bamboos be-

wilder us, and the newly accepted theories of evolution of these grasses fascinate us. Fear of invasive species keeps bamboo out of some gardens, and yet the fast rates of growth, sheer verticality, erosion control abilities, and colorful variegations make many bamboos excellent choices in many situations. It is a plant of wonder, and of extremes. With the ability to withstand below-{freezing temperatures on a university campus in Minnesota, stabilize the earth on a riverbank in Louisiana, or create realistic habitat and food for zoo animals, bamboo

can grace almost any

landscape. The many attributes of the many bamboos make it absolutely vital to our ever-changing, ever-threatened world around us. This book is a great asset for any landscape architect challenged with site considerations.

8

Foreword

It’s about time we had a resource such as this book. In addition to our native bamboo

species,

hundreds

of bamboos

have

introduced

been

into the United

States, starting as early as the first half of the 19th century. Led by Floyd McClure of the U.S. Department of Agriculture, a very active period of introduction occurred between 1924 and 1940. Today, more than 354 kinds of bamboos (species, subspecies, varieties, forms, and cultivars) can be found growing within the United

States. And yet only now can we hold in our hands a complete book about growing bamboo in America, written by an American who has actually grown bamboo in his garden. In February

1928, the USDA

published a leaflet (No.

18) entitled Bamboos and

Bamboo Culture, which stated, “One of the primary objects of this leaflet is to en-

courage home production of species suitable for the establishment of groves and gardens.” Ted Jordan Meredith essentially says the same thing throughout

these

pages in a way no one has done before. His personal experiences add immensely to the understanding of bamboo. The reader learns exactly how a bamboo grows and why.

The usefulness of bamboo goes far beyond being

just another plant in our gar-

den palette. It can be (and is) grown for its utility: poles for building, stems split for weaving baskets and crafts, shoots for culinary nourishment, leaves for animal forage, a vigorous root system for the uptake of wastewater effluent, and stabilization of disturbed soils. The buzzword of “sustainability” is a given when one speaks of bamboo. It gives far more than it takes. It is no wonder that finally now, after a century of growth in the United States, bamboo is gaining attention. Ted is an accomplished author, but also an accomplished bamboo grower, and his practical experiences Stories of success and

weave

throughout

this book

as interesting anecdotes.

failure help increase our understanding

of how

to grow

bamboos in our landscapes, and as a result of Ted’s insights, the culture section of

this book is extremely helpful. As he says, “Bamboo

is far more adaptable than

once assumed.” This book is a resource for anyone, anywhere, who wants to know about bamboo. It tells us how to buy bamboo, how to propagate it, how to harvest edible shoots, how

to control its spread, and

how

to get rid of bamboo

when

it

overtakes its bounds. These are some of the many questions I have been asked, or posed myself, during the past decade of my interest in bamboo.

I have a collection of books re-

lating to bamboo, but not one concise reference that I can refer to when asked the plethora of questions that come my way. My best reference has been through my involvement with the American Bamboo Society, but now, when asked, not

Foreword

only can I suggest membership

to our Society, but I can also highly recommend

this book. People want to know more about bamboo,

for one reason or another, and the

appropriate literature has been lacking. This book constitutes perhaps the most comprehensive assimilation and synthesis of research on bamboos, including the most recent research papers, of any bamboo book intended for non-scientists. The comprehensiveness and technical rigor of the book are a result of this tremendous effort. With

bamboo

more

than

1200 types growing across this planet, there may just be a

for every situation. The past 20 years have brought new introductions

into our country; bamboos

originating from parts of Asia, Central America,

and

South America have been imported in hopes of expanding the usefulness and aesthetic qualities of bamboos for our landscapes. And yet, bamboos without names

still exist in some habitats around the world. And still, there is so much to learn. Bamboo

for Gardens will help sort out the marvelous world of bamboos for those

simply curious, for those who are in need of help, and certainly for those who repeatedly look to bamboo for answers to everyday challenges. Read it and realize bamboo’s potential. SUSANNE LUCAS

President, American Bamboo Society

S

Preface

1 CAME

TO THE

WORLD

OF BAMBOO

not because I was attracted to, or even

aware of, bamboo’s great intrinsic beauty (though that profound enchantment would soon follow), but out of a suburban necessity. For more than a decade,

I had enjoyed, and taken for granted, an expansive

greenbelt as an extension of my backyard, and a refuge from an increasingly congested suburban environment.

Much

to my naive surprise, the expansive green-

belt was suddenly cleared away, along with the hummingbird nests and assorted wildlife. Space, in the developer’s context, is that which should be filled. Unused space is wasted space, and zoning requirements,

in the developer’s view, already man-

date a great wastage of space. My

view

was somewhat

different.

How

could

the foundation

home be laid so impossibly close to my property line? Surely,

for the new

a mistake—and one

that was starkly evident, since all trees and natural vegetation had been eliminated. Of course, it was not a mistake. Nor was it a mistake that the new homes were two stories high, to better make use of the space. As the builders framed in a large second-story window in perfect position to look down

upon

me and

lay bare my

now

absent privacy, the certainty of this

new, harsh reality had settled upon me. To my great regret, and in spite of obvious appeal, violent and destructive actions seemed neither practical nor productive. I went looking for a rapidly growing, tall, evergreen screen. I found bamboo.

Acknowledgments

1 LOOK

UPON

MY ROLE

in this book not as one of an expert, for

1am surely not

that, but as a gatherer and assembler of information from those who are experts, or who have special knowledge or expertise in a given area, whether it be arcane taxonomic issues, or skills propagating difficult bamboos, or the aesthetics and methodologies of landscaping—and all manner of topics beyond and between. My goal in this project is to assemble, synthesize, and arrange some of this wealth of information so that it is readily assessable to a broad range of garden and

bamboo enthusiasts. For much of the world’s population, bamboo is an economically and aesthetically compelling plant. For much of the Western world, bamboo is misunderstood, ignored, or reviled. It is my hope that this book will contribute to a better understanding and appreciation of bamboo. Both directly and indirectly, through written materials and personal communications, many

people have contributed to this book. The bibliography reflects

the written works by some of these individuals, but the help and assistance goes far beyond _what

is included in that listing.

In particular, I want to acknowledge the technical reviews that have broadened and deepened my understanding of bamboos, and which greatly benefited the content of this book. Lynn G. Clark, professor of botany and director of the Ada

Hayden Herbarium at Iowa State University in Ames, generously and graciously gave her time responding to my inquiries and completing a technical review of the manuscript. The landmark research conducted by Dr. Clark and her colleagues

14

Acknowledgments has redefined the origins of the grass family and the origins of bamboos. Among her numerous publications, Clark is co-author of American Bamboos, a comprehensive study of the bamboos of the Americas. Previously, relative to Old World

bamboos, very little had been written about the bamboos of the New World. Amer-

ican Bamboos fills a glaring gap in the literature and is an essential book for the library of any enthusiast or student of bamboo.

Chris Stapleton of the Royal Botanic Gardens, Kew, is a foremost expert on Old World montane bamboos. These beautiful bamboos are a dizzying taxonomic muddle. Stapleton’s research and publications have brought a measure of stability and a great deal of clarity to the taxonomy of these bamboos. I want to thank Dr. Stapleton for his assistance with numerous

taxonomic issues, and for his re-

view of the sections in the manuscript on the Old World bamboos. Apart from his books and technical papers, Stapleton also writes articles for bamboo

enthusiast

publications in both Europe and America. He is exceptionally skilled at rendering

technically complex issues in a way that they can be readily assimilated by a wide audience. I also wish to thank the president of the American Bamboo Society, Susanne Lucas, for reviewing the section of the manuscript on the society and for offering

helpful suggestions, which I have gladly incorporated. While it is essential that by Clark, Stapleton, and

| acknowledge the careful reviews of the manuscript

Lucas, and acknowledge

the benefit of the added

rigor

that has been brought to bear on the work, it is also essential for me to state that

the final wording of the manuscript is mine, and that I have sole responsibility for any and all errors that may appear in the book. In various ways, Ned Jaquith, George Shor, Gib Cooper, and Jesus Mora have assisted me with valuable advice and information. And

in a very genuine sense,

I have encountered in the American

virtually everyone

the bamboo community

throughout

the world,

Bamboo

has contributed

Society, and in insight and

in-

formation. 1am

grateful

for the cooperation

and

assistance of Quail

Botanical

Gardens,

Hakone Gardens, and Bamboo Sourcery nursery in obtaining many of the photographs.

I regret that time constraints did not permit

me to photographically ex-

plore other public gardens, as well as the many excellent bamboo nurseries. Ironically, some of those that I missed are closest to my residence. I would be rem

not to acknowledge Carol Giberson, who introduced me to

the world of plants and gardening. Had I not been so absorbed by this newfound compulsion,

I may never have encountered bamboo.

Her steadfast support, for-

Acknowledgments

bearance, and counsel during this sometimes seemingly interminable book project has been more than welcome. And

I very much

want

to express my appreciation

for my parents,

Edward

and Nelva Meredith, who encouraged me in my writing efforts from my earliest years. My father also taught me the art and science of photography, and propelled my enthusiasm for the craft. I still recall, quite vividly, my first encounter with the mysterious alchemy of the darkroom, where in the dim red glow, from the pho-

tographic paper’s white void, images of the world magically appeared. Thanks!

15

CHAPTER

1

Bamboo and the Grass Family

IT IS STARTLING TO THINK that giant timber bamboos, up to 1 ft. (30 cm) in diameter and more than

100 ft. (30 m) tall with structural properties that compare

favorably with steel, have any kinship with the fine, velvety mat of the suburban putting green—but they do. Like the putting green lawn, bamboo is a grass. The grass family, Poaceae (Gramineae), is one of the largest and most diverse,

consisting of some 650 genera and 10,000 species. Grasses are characterized by a jointed stem called a culm. Leaves emerge alternately, at the joints, in two ranks

along the stem. The leaves consist of a leaf sheath surrounding the culm, and a leaf blade growing free of the culm. Leaf veins are usually parallel. The culms are typically hollow, but they can be solid. Each culm section starts and ends with a solid joint called a node. Nodes are usually visible as a swelling encircling the culm. The sections between the nodes are called internodes. The culms of most grasses have

high silica content and are shiny. These aforementioned features are characteristic of all grasses. In the case of the giant timber bamboos, we see the typical grass characteristics played out on a grand scale. Bamboos are members of Bambusoideae, a subfamily of Poaceae. The great diversity of Bambusoideae bespeaks a long period of highly adaptive development. Bamboo

forms include delicate,

fernlike, tropical, herbaceous

plants, perennial

groundcovers, shrubs, vining climbers, and arborescent timber bamboos. For our modern world, these enduring grasses offer us great beauty and utility.

At least 90 genera and 1200 species of bamboos are distributed throughout the

17

18

Chapter

1

world’s temperate, tropical, and subtropical regions. A highly diverse member of the grass family, bamboos grow from sea level to high mountainous regions. Some

groundcover bamboos reach a height of only a few inches and can be mowed like a lawn. At the other end of the scale are timber bamboos that live up to their name, growing like timber and forming towering forests. These giant grasses are harvestable for construction, paper pulp, and food. The uses for bamboo

number

literally

in the thousands.

Bamboo is a principal defining element

for many

traditional cultures. Bamboo

is shelter. It is food, and the means to acquire food. From womb is the source of both physical and spiritual sustenance—the

to tomb, bamboo

fiber of life.

Bamboo also offers many benefits for modern societies. Among them, bamboo is a prodigious and rapidly renewable source of fiber. Even as the world’s forests and habitats rapidly decline, bamboo offers some solutions. As yet, however,

this

offer is largely unheard, and bamboo itself is at risk in many parts of the world, from unmanaged

use by dense populations and from indiscriminate land clearing.

The destruction of land and habitats in South America is most heinous. Some species have already disappeared

Dendrocalamus giganteus,

Quail Botanical Gardens.

from the face of the earth forever.

new shoots and culms at the perimeter of the clump

Bamboo and the Grass Family

And

of its benefits to modern

societies,

it must

be said that

ultimately

no

amount of conservation or clever use of resources will provide a solution for the accelerating growth and geometric expansion of the world’s population. This finite earth will one day run out of resources and space to hold the population, let alone offer a quality of life. Until world population growth is brought to a halt, any “solutions” will, in the end, be as effective as bailing out the ocean with a sieve. Bamboo can play a role in cushioning this confrontation with the finite limits of our earth, and perhaps, one day, play a role in our recovery.

A plant of uncommon beauty, bamboo is extraordinarily strong and extraordinarily delicate. In its mature form, Phyllostachys heterocycla {. pubescens is the largest temperate-climate bamboo, of 7 in. (18 cm), with

reaching a height of 90 ft. (27 m) and a diameter

masses of tiny leaves that shimmer

Except for the giant oceanic kelp, bamboo (Liese 1991). New bamboo

in the slightest breeze.

is the world’s fastest growing plant

culms can grow more than several feet in a 24-hour

period, reaching most of their full height in 30 days. It is literally possible to watch bamboo grow.

Bamboos first developed as forest plants, or along the forest margin, evolving into a highly diverse and distributed group. Bamboo is native to all but two of the

world’s continents—Europe and Antarctica. Although not native to Europe, bamboo is widely grown there as an ornamental. France and Germany

have major

commercial bamboo nurseries on a scale unknown in the United States. Not unexpectedly, the bamboos that are native to tropical regions are highly cold sensitive. Many suffer damage with only the slightest frost. Bamboos of the New World genus Guadua grow to 100 ft. (30 m) and a diameter of 8 in. (20 cm),

yet these giant tree grasses are damaged by even a minor frost. Other tropical and subtropical bamboos

are less cold sensitive and can be readily grown

in the

warmer areas of the United States, or on a small scale as indoor plants where the outdoor climate does not permit.

Most tropical bamboos grow in slow-spreading clumps. In the cooler temperate zones, most native bamboos spread rapidly, with new culms emerging from running rhizomes. There are exceptions. Some species of the tropical Guadua can

spread rapidly, sending up new culms as much as 20 ft. (6 m) or more away. Some species of the genus Fargesia, indigenous to China’s mountainous regions, grow in tight clumps, yet they are among the world’s hardiest bamboos, able to withstand temperatures of -20°F (-29°C) without damage. The genus Phyllostachys is preeminent among the temperate-climate bamboos. Most of the larger bamboos associated with China and Japan are species of Phyllo-

19

20

Chapter |

stachys. Comprising some 75 species and more than 200 varieties and forms, the genus offers some

of the world’s most beautiful bamboos

and some

of its most

useful. In Europe, North America, and other temperate growing regions, species of

Phyllostachys are the hardiest of the larger bamboos, and the most readily adaptable.

Origin and Distribution The world’s most ancient grasses, antecedents of today’s bamboos, were most likely broad-leaved, herbaceous, tropical forest dwellers that may have originated as early as the very late Cretaceous period or early Tertiary period some 65 million years ago. Among the grasses of today, a small, broad-leaved, herbaceous, rainforest species, Streptochaeta spicata, is among those that most closely resemble the ancient grasses. At one time, these earliest grasses were believed to be true bam-

boos, but molecular analysis reveals that bamboos originated later, probably in the Oligocene or Miocene epochs, some 30 to 40 million years ago (Lynn Clark, personal communication).

Once a matter of controversy, the molecular data now confirm that true bamboos include herbaceous as well as woody species. The woody bamboos that we

normally think of as bamboos, members of the tribe Bambuseae, and the herbaceous bamboos,

members of the tribe Olyreae, have been shown

to be mono-

phyletic; that is, they originated from a common ancestor (Judziewicz et al. 1999). The earliest herbaceous bamboos are believed to have originated in the Southern Hemisphere.

Supporting this hypothesis,

the oldest lineage of herbaceous bam-

boos is found in New Guinea. Although much is yet unknown about the evolution of bamboos, it is believed that the divergence between herbaceous and woody bamboos occurred very early in the lineage. It is speculated that, like herbaceous bamboos,

woody

Hemisphere,

bamboos

originated in the tropical lowlands of the Southern

subsequently radiating into the temperate zone of the Northern

Hemisphere. The earliest woody bamboos are believed to have had pachymorph

rhizome systems and a branch array resembling that of Bambusa or Guadua. The leptomorph

rhizome systems found in many genera likely evolved later.

The temperate woody bamboos comprise a single lineage. Arundinaria gigantea is the only indigenous species of temperate woody bamboos found in the New World. It is uncertain whether or not there were more species in the past. With the formation of mountain ranges, the tropical woody bamboos diversified and adapted to montane habitats as well as their original lowland domain. Tropical woody bamboos are less well defined than temperate woody bamboos.

Bamboo and the Grass Family

Currently available molecular data suggest an early divergence into the woody bamboos of the New World tropics and the woody bamboos of the Old World tropics. However, the morphological similarities between New World and Old World tropical woody bamboo groups suggest just the opposite. Studies already underway may soon shed additional light on the matter. Most grasses are adapted to open habitats, but most bamboos are adapted to forest environments. Woody bamboos evolved to compete for light with trees and other woody vegetation. Highly effective in this regard, they are important players in forest dynamics. Bamboos may grow in dense thickets or tall forests, dominating and excluding other vegetation, or exist as understory plants in a forest environment. Running bamboos, with their ability to space culms widely apart, are more likely to dominate the understory or overstory of their habitat. Clumping bamboos with closely spaced culms are more likely to coexist with other plants of similar height, though they too may dominate habitats.

A few bamboos are

climbing or clambering and may overwhelm existing vegetation. In arid areas, bamboos are more likely to be distributed in sites where more moisture is present, such as stream banks, ravines, and gullies. Europe and Antarctica are the only continents without indigenous populations of bamboo,

yet since their introduction into Europe, bamboos

have flour-

ished in many areas from the Mediterranean to the Arctic Circle in Norway. Indeed, bamboo

may have been indigenous to Europe several million years ago,

before disappearing with the Ice Age during the Pleistocene epoch, though this is highly speculative (Liese 1999). If true, this would leave Antarctica as the only continent untouched by this remarkable grass. Bamboo’s broad distribution is rather surprising, especially considering that these are evergreen plants with shallow root systems, and thus structurally are more vulnerable to cold and other climate extremes. Although, the most concentrated

populations of bamboo

not surprisingly,

occur where ample

warmth

and

moisture are available, bamboo can be found in widely disparate regions and climates. Natural bamboo

distributions range from the tropics to temperate zones,

and from approximately 50°N, where Sasa kurilensis is found on Russia’s Sakhalin

Island, to 47°S, where Chusquea culeou grows in southern Argentina. Geologic shifts and climate changes occurring over many millions of years have led to the emergence of some species that are adapted to climatic extremes. In the New World, the genus Neurolepis inhabits a higher elevation than any other bamboo genus, with N. aristata growing in dense thickets at 14,100 ft. (4300 m) in the

Andes in Ecuador. Neurolepis is believed to have evolved relatively recently and

2]

22

Chapter

1

may have originated during the uplift of the northern Andes about 5 million years ago (Judziewicz et al. 1999).

Although we usually have woody forms in mind when we think of bamboo, approximately

110 species of herbaceous bamboos exist worldwide. Of these, all

but two are indigenous to the New World. Most are found in moist forests below 3300 ft. (1000 m) but may occasionally occur at elevations of up to 8900 ft (2700

m). They range from 29°N to 34°S latitude (Judziewicz et al. 1999). Of the approximately 90 bamboo

genera,

some

70 are woody

bamboos.

Of

the 70 woody genera, 21 are native to the New World, and some 50 are native to the Old World. The genus Arundinaria, as currently constituted, is the only genus native to both the New World and the Old World. The New World has approximately 430 woody species, the Old World approximately 500 to 600 species. When

all bamboos, including herbaceous ones, are considered, the numbers of New World and Old World species are roughly equal

(Judziewicz et al. 1999). The New

World genus Chusquea is estimated to comprise more than 200 species, more than

any other bamboo genus. Bamboo distribution can be characterized by its presence in three major geographic regions:

Asia-Pacific, the Americas, and Africa. The Asia-Pacific region is

the most well known and well developed bamboo region, with some 800 species and varieties and some 45 million acres (18 million hectares) of bamboo. Some of

the regions and countries

in the Asia-Pacific are China, Japan, Korea, Southeast

Asia, India, Australia, New Zealand, and the Pacific Islands. The Asia-Pacific region can be roughly divided

with pachymorph

into two subregions based on rhizome

rhizomes and a

habit. Bamboos

typically clumping habit are distributed pri-

marily in the warmer areas between the Tropic of Cancer and the Tropic of Capricorn.

Bamboos

with leptomorph

rhizomes and a running

habit generally have

much greater cold resistance and are distributed at higher latitudes, in such regions as Japan,

Korea, and the Huang

(Yellow)

and

Chang

(Yangtze)

China. In China, bamboos with leptomorph and pachymorph

River valleys of

rhizomes are dis-

tributed in roughly equal numbers. China is one of the world’s great centers for indigenous and cultivated bamboo.

Some 400 species and 40 genera are native to

China. Great forests of timber bamboo flourish in parts of the country, and bamboo is integrated into the modern economy as well as traditional culture. Herbaceous bamboos are absent from China. The African region is relatively small, with limited extension, nearly entirely in tropical areas, ranging from southern Senegal in the north to southern Mozambique and the island of Madagascar in the south. Although the continent’s mainland

Bamboo and the Grass Family

has fewer than

10 species and only 3 genera, Madagascar is home to some 11 gen-

era and 40 species. Many genera are common

to both Africa and the Asia-Pacific.

In the Americas, bamboo occurs naturally from the southeastern United States in the north to the beech forests of central Chile in the south. South America was likely the center of origin for most New World woody bamboos, with subsequent migration to Central America and Mexico after formation of the Panamanian land

bridge some 5.7 million years ago. Species indigenous to Central America and Mexico are probably of more recent origin (Judziewicz et al. 1999). Although

the Asia-Pacific region is often assumed

to be predominant

in the

world of bamboo, the Americas are nearly as rich in genera and species, exhibiting a greater range of structural and evolutionary diversity. The Americas have an esti-

mated 41 genera and more than 500 species of bamboos, including both woody and herbaceous types. Chusquea is distributed across a wider latitudinal range than any other genus. Guadua covers enormous territories of up to nearly 47,000 square miles (122,000 square kilometers)

in the Brazilian Amazon

and Peru

(Londono

1996).

Except for a few species of the unusual genus Chusquea, the only leptomorph bamboos in the New World are Arundinaria gigantea and its subspecies, which is also the only bamboo native to the United States. Herbaceous bamboos are nearly exclusive to the Americas, existing primarily as tropical understory plants, and often somewhat resembling ferns or ginger. Most of the New World bamboos, including the woody types, are relatively small, but there are highly notable exceptions, such

as the tropical giant, Guadua angustifolia, which easily rivals its Old World timber bamboo counterparts in both size and importance to the local economy. Although some researchers placed bamboo’s origins in southern China, other evidence indicates a different origin. A study using chloroplast DNA, and analysis of the cladograms that emerged the Southern Hemisphere, introductions,

all current

from the study, placed the origins of bamboo

perhaps in South America. South

American

though the South American bamboo

in

Except for recent human

genera are unique to the region. Al-

Guadua was once thought to be part of the

Bambusa genus of India and Asia, it is now known to be a distinct genus. Southern Asia, arguably the world’s greatest bamboo

resource, was not bam-

boo’s center of origin, but probably a later, emergent center with highly amenable climatic conditions. As molecular sequence studies become more comprehensive,

we may learn much more about the origins and distribution of the world’s bamboos. For now, much is a matter of speculation and hypothesis. One such hypothesis, for example, contends that Arundinaria gigantea, North America’s only indigenous woody bamboo, may be the only New World bamboo of Asian ancestry,

2

24

Chapter

|

perhaps having migrated from Asia across the Bering Bridge during a period of ample warmth and moisture.

The clumping, winter-hardy, montane bamboos of the Sino-Himalayan region were once thought to have originated from bamboos that inhabited the tropical forests of Southeast Asia some 60 million years ago, subsequently evolving as the geologic uplifting gave the tropical bamboos a long, slow ride to elevations of up to 13,000 ft. (4000 m). However, evidence now indicates that the earliest bam-

boos originated long after this uplifting, and the Old World montane bamboos evolved from the temperate clade of ancestors rather than the tropical clade (Lynn Clark, personal communication). Human

introductions

have

greatly extended

bamboo’s

distribution,

to such

difficult environments as arid desert climates and the cold climate extremes of the Arctic Circle. Fargesia nitida and F. murielae have been growing in Norway for more than 30 years. Fargesia nitida has successfully survived winters in Tromso, Norway, at nearly 70°N latitude, well into the Arctic Circle (Flatabo 1995).

Some of the human introductions occurred sufficiently long ago that the bamboos are fully naturalized. Phyllostachys heterocycla f. pubescens, for example,

was

introduced into Japan from China in the 1740s and now covers some 40 percent of Japan’s total bamboo acreage. Bamboo was distributed along trade routes, including the ancient maritime spice routes between China, Indonesia, Ceylon (Sri Lanka), and India, cloaking the center of origin for some species. Bambusa vulgaris may have originated in Malaysia and Indonesia, but because it is very easily propagated and readily useful,

the species is now

widely distributed throughout

the

world’s tropical regions as a result of numerous human introductions. Oxytenanthera abyssinica, indigenous to Africa, has been introduced into India as a source of

pulp for paper. Some regions without indigenous bamboos

have climates that are neverthe-

less highly favorable to these plants. Southern France, near the Mediterranean, for

example, has stands of Phyllostachys heterocycla {. pubescens rivaling those of their native environments in Asia. The temperature ranges and precipitation patterns of the southeastern United States are highly suitable to many bamboos. The moder-

ate winter climate of America’s West Coast, from north to south, is favorable to many species. Most of the rainfall along the West Coast, however, comes primarily in the fall and winter months, while summers are relatively dry. This moisture pattern is just the opposite of the temperate bamboo growing regions of Asia, and supplemental water during the summer months is generally necessary for optimal growth.

Bamboo

and the Grass Family

Woody and Herbaceous Bamboos All bamboos belong to the grass subfamily Bambusoideae. The subfamily is comprised of two tribes, Bambuseae and Olyreae (Judziewicz et al. 1999). The woody

shrubs and treelike bamboos that we normally think of as bamboo belong to the tribe Bambuseae. Olyreae consists of the herbaceous bamboos. Although the legitimacy of herbaceous bamboos has been accepted for quite some time, recent research

has clarified several taxonomic

issues. The world’s most ancient grasses,

once thought to be herbaceous bamboos, are now known to have preceded bam-

Phyllostachys nigra var. henonis.

Bamboo Sourcery.

25

26

Chapter 1 boo. Rices are closely related to bamboos and were once thought to be herbaceous bamboos, but molecular analysis has shown that this is not the case. The woody bamboos are diverse, thriving in many different habitats, from sea level to the high mountains, across a broad latitudinal range. The herbaceous bamboos have a far more limited habitat range, centered primarily in moist forests of the New World. Though

not hardy, and with little tolerance for dry conditions,

some herbaceous bamboos are very appealing horticultural subjects and can be grown outdoors in a few regions of the United States; many more may be adequately suited to indoor or protected growing conditions, as long as the humidity is sufficient. As of this writing, only a few are available in North America. The most obvious distinction between woody and herbaceous bamboos is the

lignification or “woodiness” of the culm. Herbaceous bamboos have relatively unlignified culms and

are unable

to support

tall growth

or heavy

leaf canopies.

Woody bamboos have complex branching patterns. Herbaceous bamboos either have no branches, or else a simple branching pattern with little or no ramification.

Woody bamboos have two growth phases: first, the culm elongates, protected by culm leaves that sheath the new culm but offer little or no photosynthesis, followed by branching and the emergence of photosynthetic foliage leaves. The two phases are not always discrete. In some genera, such as Phyllostachys, the second

phase begins before the first phase is complete. Herbaceous bamboos, and all other grasses, have a single growth phase, extending photosynthetic leaves as the culm elongates. Woody bamboos have bisexual flowers. Herbaceous bamboos have unisexual

flowers

(Judziewicz et al. 1999).

The focus of this book, and, indeed, the focus of most gardeners, growers, and landscapers, is on the woody bamboos. Few herbaceous bamboos are currently cultivated, and, in the main,

they better fit our conception

of little houseplants

than they do our conception of bamboo. On the other hand, for the bamboo aficionado, there is considerable appeal in the common ancestry of the herbaceous and woody bamboos. The herbaceous brethren are the world’s smallest bamboos. Raddiella minima

has delicate culms

with the culms of some

woody

no more

than 2

timber bamboos

in. (5 cm)

that are more

tall—contrasting

than 600 times

taller and rival the strength of steel. While not likely to challenge woody bamboos for the hearts and minds of bamboo aficionados, the herbaceous bamboos deserve more attention and cultivation. Many, like the delicate, fernlike Raddia distichophylla, are certainly worthy of attention.

GVA

IE

Re2,

Structure and Function

Segmented Structure The bamboo plant consists of a series of ramifying, segmented, vegetative axes, differentiated, according to function, into rhizomes, culms, and branches. Each axis consists of a series of nodes and internodes. The axes are usually hollow along the internode and always solid at the nodal joint, thus forming a series of segments along the length of the axis, whether the axis is a culm, branch, or rhizome. Roots are the only vegetative axes of a bamboo plant that are not segmented. Buds, nascent branches, or rhizomes are present at most nodes. During the period of active growth,

and

sometimes

persistently, the segments are covered

by

leaves or bracts that subtend the bud, protecting it and the internode that arises from the node. Like the buds, the leaves or bracts face alternating sides of the axis

along its length. Although the aboveground part of the bamboo plant is differentiated by function from the underground part of the plant, the structures are generally parallel, particularly for bamboos with leptomorph

rhizome systems. In

some species, roots or root primordia are even present on culm and branch nodes. The segmented structure plays a major role in giving bamboo its special char-

acteristics. The hollow internodes, common to most bamboos, and solid nodes are fundamental elements in bamboo’s notable combination of light weight and great strength.

27,

———

node a

fh)

internode

—

supranodal ridge

sheathscar

sulcus

branch

branch complement

Figure 1, Segmented structure and features of a bamboo culm. The pronounced sulcus that runs the length of the internode is characteristic of Phyllostachys.

Structure and Function

Neck The neck is usually associated with the rhizome, but it is a structural element of every segmented axis of the bamboo plant. The basal portion of an axis, the neck, consists of tightly compressed segments, usually smaller in diameter than the portion of the axis that follows. Along the neck, the nodes lack buds, and the reduced leaves are small and scalelike. On the branches of many species, the neck is nearly absent. The neck is more obvious at the base of culms and rhizomes, where the structure does indeed more typically resemble a neck.

Structurally, the neck permits creation of a new and larger axis. The highly compressed stacking of progressively larger internodes can create a new axis much larger than the axis from which it originated. This is well illustrated by the rhizomes and culms of leptomorph timber bamboos. The rhizomes are proportionally

much smaller in diameter than the culms (new axes) they generate. The highly compressed internodes of the neck progressively increase in diameter to form the base of the culm. Like other parts of the plant, the neck has developed in specialized ways in response to environmental conditions. The rhizome necks of the pachymorph bamboo Yushania macrophylla, for example, are completely hollow, even at the nodes,

forming long conduits. This feature may have evolved in response to the seasonally waterlogged conditions of its native environment. The rhizome neck or culm neck of a leptomorph bamboo is usually short and

plays a limited role in the function of the plant. For bamboos with pachymorph rhizomes, however, the neck may serve additional functions, such as establishing support for the culms, and accelerating the spread of the plant. Evident at even the seedling stage, the necks of pachymorph

rhizomes typically first turn downward

before turning upward to form a rhizome and culm. This initial downward

turn

serves to establish the new, larger culm more deeply in the soil. The large, tropical pachymorph

bamboo

Guadua angustifolia initiates the neck portions of new

rhizomes and culms early, creating feet that penetrate into the soil and help support the towering 100 ft. (30 m) culms. In this species and others, a highly elongated neck allows the bamboo to greatly extend its reach, creating an aggressive spreading habit rivaling that of the larger leptomorph bamboos.

Node

All the jointed axes of a bamboo plant consist of a series of nodes and internodes. The node is always solid and is frequently marked by a swelling of the axis. In

20)

30

Chapter 2

early Japanese horticultural texts, the swollen node was said to resemble a crane’s

knee. All the cells along the internodes are axially oriented—that

is, they run

along the length of the internode—and are devoid of radial cell elements. Only at the nodes do the cells turn inward across the nodal diaphragm. New

axes only occur at the node,

never along the internode.

For example,

branches are initiated along the culm only at the nodes, secondary branches only at the nodes of the main branches, and so on. Branches, culms, and rhizomes are initiated from buds at the nodes on alternating sides of an axis. On a culm, for example, a bud elongates into a branch or branches on one side of the culm, and the bud and branch complement

at the node above it emerge from the opposite side

of the culm.

Internode In bamboos and other grasses, the internode is the portion of the culm, branch, or rhizome between the nodes. Internodes are usually hollow, but they can be solid, as is the case with

most

shoot is cut in half along

Chusquea.

If

a bamboo

its length, a series of com-

pressed nodal diaphragms will be apparent. As the shoot

elongates and develops

into a culm,

the

short walls of the diaphragm elongate, form the internode, and give bamboo its height. The

length

of a culm’s

internodes

typically

(though not always) first increases, then decreases toward the tip of the culm, with the longest internodes

found

around

mid-culm.

Severely

com-

pressed internodes near the base of some culms is a distinguishing characteristic of Phyllostachys aurea. The internodes of some P. aureosulcata culms are markedly kinked near the base, an attractive ornamental feature. Internode

length

varies

among

species.

The

somewhat short internodes of Phyllostachys heteroLeft: A colored portion are the tion of

new Phyllostachys bambusoides culm. The lightrings are the sheath scars, marking the lowermost of each node. The slightly raised rings, just above, supranodal ridges, marking the uppermost poreach node.

Structure and Function

cycla {. pubescens contrast with the relatively lengthy internodes of P. rubromarginata. Internode

length,

however,

is not a singular determinant

of maximum

height. Phyllostachys heterocycla f. pubescens is the tallest of all running bamboos. Arthrostylidium schomburgkii, an arcane species found in remote Venezuelan mountains, has exceptionally long internodes extending up to 15 ft. (4.5 m). It was prized by indigenous peoples for use as blowpipes to shoot poisoned arrows.

Sheath scar A sheath scar surrounds the stem at the node, marking the attachment point of the culm leaf sheath. The sheath scar is the lowermost portion of the node. In some species the sheath scar is inconspicuous.

In others, it is prominent

and

sometimes hairy. The sheath scar may symmetrically encircle the culm, or it may dip conspicuously on the side where the branches emerge. It is an ornamental

and distinguishing

feature of

bamboo.

Sulcus The culm, branch, and rhizome internodes of the genus

Phyllostachys

are distinctive.

A pro-

nounced groove throughout the length of the internode is caused by the presence of a developing branch bud at the base of the internode, grooving the culm as it elongates. Other bamboos have only partial grooving, or none at all. Right: The sulcus, dark green in this example of Phyllostachys aureosulcata f. spectabilis, is the groove formed when the developing branch bud is held tightly to the extending internode by the culm leaf sheath. The bud has emerged to form a branch, which will reiterate the principal parts of the culm—nodes, internodes, and so forth. The sheath scar is just below the new branch. The supranodal ridge is pronounced in this species and is highlighted here by a brownish red coloration.

At the lowermost portion of the node, the culm leaf sheath peels away, revealing the sheath scar.

31]

52

Chapter 2

The groove is called the sulcus. As with the buds and branches, the sulcus alter-

nates from side to side along the culm’s length. The sulcus is distinctively colored in some species and cultivars. For example, it is yellow in P. aureosulcata and dark purple-brown in P. nigra ‘Megurochiku’

Supranodal ridge The supranodal

ridge delimits the uppermost

portion of the node. In some bam-

boos, the culm is marked by a pronounced ridge at the node, just above the sheath scar. Significant variations can occur among bamboo of the same genus. Phyllostachys rubromarginata, for example, has minimal swelling, whereas P. nidularia has a very pronounced supranodal ridge.

Rhizomes For bamboos with a pachymorph

rhizome system, rhizomes may appear as little

more than the short curved base of the aboveground culm. For bamboos with a leptomorph rhizome system, rhizomes are underground stems that extend the domain of the parent plant and serve as a nutrient storage system for the rapid growth of the culms. Roots emerge from the nodes of bamboo rhizomes. The aboveground culms in a clump or grove of leptomorph bamboos do not exist in isolation, but are interconnected through an underground system of rhizomes, the primary energy store for the plant. A study based on carbon cycling in Phyllostachys bambusoides demonstrated

the interrelationships of photosynthetic

activity and energy storage and demand (Isagi et al. 1997). When photosynthetic activity creates a surplus, the surplus is stored in the rhizome system. When

pho-

tosynthetic activity is insufficient for the plant’s needs, the plant draws upon the energy stores in the rhizome system. If the rhizome system is unable to meet the needs of the plant, the plant begins killing part of the culms to reduce the plant’s

needs and reestablish equilibrium. To the extent that a young grove has developed from a single bamboo plant that has not been divided, the entire grove is a single organism, gathering, storing, and disseminating nutrients for its growth. The rhizomes of leptomorph bamboos are remarkable. The rhizome of a large species from a well-established grove can

extend as much as 25 ft. (7.5 m) ina single season of growth. The structure of this underground stem parallels that of the aboveground culm, but the rhizome internodes are much shorter, and the nodes thus more frequent. Arranged horizontally and alternating from side to side, the buds at each node offer the possibility of

Structure and Function

new

culms and

new

rhizome

branches. The

into still more rhizomes, which

lishing an interwoven season of growth,

extending

rhizomes branch

in turn extend rapidly and branch, quickly

network.

soil, generally on top of older

rapidly

New

rhizomes grow

close to the surface of the

rhizomes, and over and under

the rhizomes

form a denser

weave.

estab-

each other. With each

The ground

under

established grove is an impenetrable mass of roots and interconnected

a well-

rhizomes

several feet thick Where

erosion and soil stability are a concern,

nothing betters bamboo,

par-

ticularly leptomorph bamboos, for protecting and binding the soil. Bamboos with pachymorph

rhizome

systems

are also excellent

in this regard

and

are often

planted for this purpose in tropical environments.

It is often written in bamboo lit-

erature that

to run into a bamboo

Japanese

mothers

tell their children

grove in

case of an earthquake—“there is no safer place.” It is one thing to read such anecdotal tidbits and another to be impressed at how

ubiquitous this maternal indoc-

trination must be. I was in a sushi bar in the United States, talking idly to the sushi chef about

bamboo,

and

he said, “If there is an earthquake,

grove. It’s the safest place.” Leptomorph proximately

rhizome

60 percent

cell

tissue consists

parenchyma,

of ap-

or generalized

cell tissue, 20 percent sclerenchyma, long-celled struc-

tural fibers, and 20 percent conductive tissues in the form of vascular bundles (Ding et al. 1992). Some species, such as Phyllostachys heteroclada, P. nidularia,

and

the native North

ssp.

American

Arundinaria

gigantea

tecta, have rhizomes with air canals, suggesting an association with a watery environment

during the evo-

lutionary process. Bamboo

rhizomes are segmented, and the leaves

are reduced, consisting primarily of a protective sheath, or bract, that surrounds the rhizome, once again par-

alleling the structure of the aboveground culm. The rhizome’s bracts are vital to the growth

of a rhizome,

Right: The tip of a Chusquea rhizome. The tightly overlapping scalelike leaves, or bracts, protect the rhizome during its elongation and growth. The leaf blades, having no photosynthetic purpose, are highly reduced to a hard, pointed, beaklike

structure.

run

into a bamboo

33

34

Chapter

2

protecting it as it penetrates the soil. The inner surface of the bracts is smooth and polished, allowing

the growing

rhizome

to slide forward

as each

internode

ex-

tends. The leaf blade is highly reduced and may be apparent only as the hard tip of the bract. The tip of the rhizome is hard, pointed, and beaklike. Its design protects the critical growing

tip from

damage

and allows

ready

penetration

of the soil.

When confronted by an obstruction, the hard, smooth point finds cracks in the ob-

stacle or readily diverts around it. The rhizome tip secretes moisture as it grows, making penetration of the soil easier. The depth of a new

leptomorph

rhizome depends on the condition of the soil

and the habitsof the species. If a layer of moist, loamy soil rests on topof a harder

concrete-like base, the rhizome will tend to stay in the loamy soil layer. In poor soils, the internode may vary greatly

in length and diameter. Some

species, such

as Semiarundinaria okuboi or some of the larger species of Pleioblastus, have highly invasive tendencies, with deep,

fast-running rhizomes.

Others, such as the large

A rhizome section from a Phyllostachys bamboo. A new culm shoot is emerging. The sulcus on the internode, characteristic of Phyllostachys culms, is also present on the rhizome internodes. The roots are attached at the rhizome nodes.

Structure and Function

timber bamboo species of genus Phyllostachys, run close to the soil surface. In gen-

eral, the new rhizomes of most leptomorph bamboos are within the first foot (30 cm) of soil, and more typically within the first 6 in. (15 cm). In an older grove, the rhizome mass may be much

thicker, but the viable rhizomes will remain close to

the surface. Running so close to the surface of the soil, leptomorph rhizomes commonly encounter an obstacle or change in soil depth that causes them

to break into the

air before penetrating the soil again. Occasionally, and most frequently in a young planting,

the tip of a leptomorph

rhizome

turns up and grows

into an above-

ground culm. These whipshoots will tend to be more curved, stand less erect, have shorter internodes, and be smaller than culms emerging from buds on a rhizome. Just as a rhizome may break above ground and turn into a culm, a culm may turn downward into the ground and become transformed into a rhizome with the ability to generate new rhizomes, culms, and roots. How

do you

know

the orientation of an underground

rhizome?

For Phyllo-

stachys, and probably most leptomorph bamboos, the branches emerge from the sides that are roughly parallel to the axis of the rhizome.

Roots Roots are the only bamboo axes that are not

segmented and not protected by a sheathing organ. They grow from rhizome nodes and the nodes of the underground portion of the culm. The roots at the base of the culm are structured differently. They primarily serve to anchor the culm and prevent it from toppling over

in

the

wind,

rain,

or

snow—or

the

weight of its own leaves. The roots are typical of grasses:

fibrous,

relatively

equal

Right: Usually not as exposed as shown

in size,

here, the

roots at the base of the culm of this new Phyllostachys decora shoot are a showy, bright reddish pink. Unlike the roots that grow from the rhizome, which function primarily in the uptake of moisture

and nutrients, the roots at the base of the culm function primarily to anchor and stabilize the culm.

35

36

Chapter 2

without ramified orders. Most roots are concentrated in the upper foot (30 cm) of soil. Bamboo

roots can also store starches, though

the rhizomes are the chief un-

derground repositories for starches. Because of their extensive network of rhizomes, leptomorph

bamboos are

perhaps the world’s best plants for erosion control. Pachymorph bamboos lack an underground network of rhizomes, but their root systems extend up to six times the diameter of the clump, making them useful for erosion control as well. In Indonesia, in steep terrain, pachymorph

bamboos are planted along the banks of

newly bulldozed roads to prevent erosion and slippage. The roots of some bamboos have become modified in adaptation to environmental conditions. Thamnocalamus spathiflorus var. crassinodus, for example, has unusually large, succulent roots, which

may be an adaptation that permits more ef-

fective water storage in dry soils and environments. P/yllostachys atrovaginata and P. heteroclada, on the other hand, have air canals in their roots as well as their rhizomes, an adaptation to wet or boggy soils that would otherwise not permit growth. In a few, usually tropical species, root primordia may appearon aboveground nodes of culms and branches. Aboveground root primordia tend to be most evident on the lower nodes, decreasing toward the culm’s apex. In Chimonobambusa quadrangularis,

a moderately hardy running bamboo,

the aboveground

root pri-

mordia dry and harden, giving the appearance of spines or thorns.

Culms In all but a few species, the culms of bamboo are hollow, except at the node. As in most monocots, the stem does not thicken but emerges from the ground at its final girth. Maximum height is achieved in a single growth period. The culms of most pachymorph bamboos typically require several months or more to attain

their full height. Leptomorph bamboo culms race to their full height in five to eight weeks. Most of the growth is accomplished in a three- to four-week period. The most rapid spurt occurs at approximately half the culm’s final height. In a mature grove of the larger species of running bamboo, this growth habit can be quite spectacular, as new shoots, a half-foot (15 cm)

in diameter, break through

the soil and thrust skyward at a rate of a yard or more a day. The particular species determines the maximum growth parameters, but growing conditions, and the age and size of the grove, determine culm size at a given site. A grove of large leptomorph bamboo requires 10 to 15 years to produce

culms of maximum size, pachymorph bamboos typically less. Smaller species gen-

Structure and Function

erally attain maximum size more quickly. In a developing grove, the largest culms are usually the youngest. Older culms are smaller, reflecting the less mature and more limited capacity of the grove when they were produced.

Anew culm rapidly hardens as it emerges from the soil, quickly strengthening to support itself as it thrusts skyward, and to support the branches and leaves that

will soon follow. Maximum strength, however, is not achieved until at least the end of the third growing season, or longer for some species. The lifespan of an individual culm varies, but 10 years or less is common. The culms of Phyllostachys bambusoides, a leptomorph bamboo

prized for the stength and size of its culm

wood, can live for at least two decades. Culms of Chusquea culeou have been estimated to live up to 33 years. Most bamboos flower at lengthy intervals. When this occurs, the otherwise healthy culms lose strength and become brittle. Small culms taper from base to tip. Large culms of some bamboo, notably spe-

cies of Phyllostachys, increase in diameter before beginning a long, gradual taper to the tip. Some species taper more rapidly than others. Phyllostachys rubromarginata,

for example, tapers less rapidly than P. dulcis. Ata given maximum culm diameter, P. rubromarginata will reach a greater height than P. dulcis.

Culms are generally green, but the coloration and features are striking and distinctive in many species and forms. The outermost three layers of cells in the de-

veloping shoot are normally green but can have other coloration, resulting in bamboos with yellow culms, such as Phyllostachys bambusoides ‘Allgold’, yellow culms with a green sulcus, such as P. bambusoides f. castillonis, and green culms with a yellow sulcus, such as P. bambusoides f. castillonis-inversa. Other culm color variations are possible. Phyllostachys viridis ‘Robert Young’ begins a sulfur green with a few darker green stripes along the internode. The stripes remain green, but the culm turns sulfur yellow, then old gold. Phyllostachys bambusoides f. castillonis does not go through an initial color shift but is already straw yellow with a green sulcus when the culm leaves fall away. Some bamboos with yellow culms, such as P.

aureosulcata . spectabilis and Semiarundinaria yashadake {. kimmei, may take on a range of red color tones, helped by exposure to sun and cold, turning a vivid brick red then changing back to yellow again with

the changes of seasonal climates.

Phyllostachys nigra turns a deep purplish black with age. The culms of P. nigra ‘Bory’ become spotted or blotched with dark purple-brown to black areas. The culms of

P. nigra ‘Megurochiku’ remain green, except for the sulcus, which turns a chocolate brown.

Shapes vary as well. The culms of Chimonobambusa quadrangularis are slightly

square, rather than round. Above each node of Pseudosasa japonica ‘Tsutsumiana’,

Si

es © gh,

ah

Phyllostachys viridis ‘Robert Young’ culms of varying age.

Structure and Function

the culm swells and then tapers, in a shape similar to a green onion. The variations in color and shape are numerous and are part of bamboo’s beauty and interest. The exterior surface of a bamboo culm has a hard, protective, waxy finish. In some species, the new culms may be coated with a waxy white powder. The coat-

ing is characteristic of the species and can range from a barely visible light powder to a thick white coating. The powder

may

cover the entire internode or only a

portion near the node. The variations in the coating of white powder and the coloration differences of the underlying culm create a range of distinctive looks among the many species. As the culm ages, the waxy bloom gradually disappears.

The waxy coatings resist moisture and protect the young culms and branches. Along the culm, only the sheath scars provide any opportunity for the passage of

liquids into or out of the culm, and this only to a minimal degree. The storage of energy reserves in the culm, in the form of starches, is generally associated with pachymorph bamboos that lack the extensive network of a lepto-

morph

rhizome system, but leptomorph bamboos store starches in the culm as

well. A study of Phyllostachys viridiglaucescens, for example,

showed

that young,

three-month-old culms contained no starch, since all available nutrients were being used, but older culms contained starch, and even culms as old as 12 years continued to have stores of starches and the ability to mobilize them.

Culm cell tissue consists of approximately 50 percent parenchyma, or generalized cell tissue, 40 percent sclerenchyma,

long-celled structural fibers, and

10

percent conductive tissues in the form of vascular bundles (Liese 1985). The culm fibers,

the sclerenchyma

cells, are much

longer

than

similar cells in hardwoods,

having a ratio of length to width of up to 250 to 1. The shortest fibers are those nearest the nodes. Befitting their different functions, the proportions of cell tissue differ signifi-

cantly from that of the rhizome. Needing to support their own weight and the masses of branches and leaves, as well as to resist the wind and other elements, culms have cell tissue consisting of twice as much fiber as in rhizome cells. Absent

the need to provide a conductive architecture for the root system, the quantity of conductive tissue in culms is approximately half that in rhizomes. Within the culm, the conductive tissues, the vascular bundles, are arrayed distinctively in patterns that can be associated with taxonomic placement at the subtribal and generic levels, and possibly at subgeneric levels in some instances.

Vascular bundles, however, are merely one characteristic among an array of char-

acteristics and are not a taxonomically defining feature in and of themselves (Wong

1995b).

32)

40

Chapter 2

The vascular bundles are smaller and more numerous at the periphery of the culm. Toward the interior, they become larger and more widely spaced. These water-conducting tissues are not renewed and must last the life of the culm. As they age, the vascular tissues become partially blocked by deposits, contributing to

the loss of vitality and eventual death of an individual culm. During the first several years of a culm’s life, the moisture content decreases significantly as the culm

matures, and it continues to decrease thereafter, although at a more gradual rate. Cellulose comprises more than half of bamboo’s chemical constituency. Lignin imparts rigidity to cell walls and is the second greatest constituent.

Lignification

proceeds from top to bottom within the internode. It is initially restricted to the culm walls necessary for mechanical support and to the tissues protecting the delicate vascular system within the culm. Limiting initial lignification to only the essential minimums

is likely an adaptive feature that allows bamboo

to achieve its

extraordinarily rapid culm growth with only minimal resource requirements. In the rapid first month year, lignification

of growth,

culm

fibers are generally unlignified.

is essentially complete,

though

lignin content

may

Within a increase

slightly in older culms. From a structural standpoint, bamboo

is a composite, a material composed of

softer, less rigid material and stronger, stiffer material. In bamboo, cellulose is the former, lignin the latter. Structurally,

a good composite is superiorto its individual

components. Although bamboo and wood are chemically similar, bamboo is approximately twice as stiff as wood and possesses far greater shear strength. In certain selected measures of strength, bamboo even exceeds the performance of steel (Janssen

1985). Modern composites, the wonders of science and technology, are

emulators of these bamboo grasses.

Branches Branches emerge at the nodes on alternate sides. Bamboo’s branching system

is

uncommon among monocots and reflects a high degree of specialization. Except in the genera Chusquea and Apoclada, which have two or more buds present at each node, all bamboo branches at a given node emerge from a single bud. Chusquea is quite unusual; in some species, the number of branch buds can number as many as 80 or more (Clark 1989). For bamboos other than Chusquea and Apoclada, the ap-

pearance of multiple branches emerging from a node arises because bamboos often

bear lateral buds so close to the primary bud that it appears many branches are

emerging independently from the culm. In these instances, the internode of the primary branch is so compressed it is barely distinguishable from its base.

Structure and Function

In bamboos, the bud or branch grouping is called a complement. The number of branches in the complement and the nature of their array is an identifying char-

acteristic. The most typical branching pattern of a species is found in the middle of the culm. Lower branches are not always fully developed. Upper branches do not

always maintain the branching pattern that distinguishes the species. Some genera have only a single branch

per node. The single branches are usu-

ally somewhat smaller than the culm and emerge at a narrow angle to the culm. The lower branch nodes.

nodes are budless. Branching buds occur only at the higher

Single-branching bamboos

are typically

shrubby, often with large leaves.

Sasa and Pseudosasa are examples of genera that usually have a single branch at each node, though most Pseidosasa bamboos are less shrublike, with a more erect,

treelike stance A complement

of two branches per node is characteristic of Phyllostachys.

Al-

though the primary and lateral buds elongate simultaneously, the primary branch remains dominant. Occasionally,

a much smaller middle branch will also appear.

The angle between the branches and culms and between the branching pair ranges

from 60° to 80°. The erect culms and branching pattern help give Phyllostachys species their imposing treelike stature.

=

al

:

New branches emerging from multiple buds on a Chusquea culm.

Branches emerging from a new Phyliostachys glauca culm. Both branches arise from a single bud.

4]

42

Chapter

2

In bamboos with three main branches per node, two lateral buds emerge from the first and second nodes of the principal branch. As with culm branches, the secondary branches emerge at the nodes on alternating sides. In this pattern, the spacing of the first and second nodes is so close that the branches appear to emerge from a common

base. The three branches elongate nearly simultaneously, but the

central, principal branch remains dominant. Species of Sinobambusa usually have this type of branch complement. A branch complement of multiple branches per node has many variations. Some genera, such as Bambusa, have a dominant

branch surrounded by several or

many smaller branches. In the genus Shibataea, the branches are relatively equal in size. In some species of Arundinaria, the lower nodes of a narrow-angled, threebranch array are budless, followed

by strong branching at higher nodes.

Other

Arundinaria species have numerous branches emerging from an apparent common base. In some species, the number of branches is determined by the maturity of the

bamboo or the position on the culm. Lower culm nodes may have none or a solitary branch, middle culm nodes three to five, and the upper nodes may have numerous

branches.

Thorns are modified branches. Most bamboos have no thorns, but those that do can be quite formidable. Several Bambusa species have thorns, as do nearly all species of Guadua, the only New World genus with thorny species.

Leaves A bamboo leaf cons

s of the sheath, blade, and ligule, and it may include auricles

and fimbriae as additional appendages.

Leaves are associated with every seg-

mented axis of the bamboo plant—rhizomes, culms, and branches. The leaf and its

parts are modified according to the function required. The prominence of the sheath and the blade varies. On the leaves or bracts that protectively encase the underground rhizome, the sheath dominates, and the blade is all but absent, some-

times appearing as no more than a hard pointed area at the tip of the sheath. With no photosynthetic function,

sheath clearly predominates,

the blade plays little role. For the culm

leaves, the

reflecting its primary role in protecting the new

culm. The blade plays only an incidental role. On the foliage leaves, however, the blade predominates, reflecting its primary function as the plant’s photosynthetic engine.

The terminology regarding bamboo leaves and sheaths has varied over time. Sometimes sheaths are described separately, as sheathing organs, rather than as

Structure and Function

part of a leaf (McClure 1966), but since the sheath itself may be green and photosynthetic, it can be properly included as part of the leaf. Given this standing, the term “culm leaf” has gained legitimacy (Judziewicz et al. 1999).

All bamboos have a similar leaf anatomy and characteristics in leaf structure that set them apart from the rest of the grass family. Though these distinguishing characteristics are not readily visible, the foliage leaves with their pseudopetioles overtly differ from

most of the rest of the grass family. The pseudopetiole

is the

stalk at the base of a leaf blade that connects the blade to its sheath. It is sometimes called simply a petiole, although this omits the distinction between the structural element of the monocotyledon

bamboo and the true petiole of the dicotyledons.

Apart from bamboos, most grasses do not have pseudopetioles. The sheath connects the blade and pseudopetiole to the branch. The foliage leaf sheath is wrapped so tightly around the branch that it is hardly distinguishable from it on casual viewing. This gives the impression that the pseudopetiole is attached directly to the branch, but it is not. Foliage leaf sheaths are much longer

auricle

* fimbriae

sheath —|1—

Figure 2. Culm leaf.

43

44

Chapter

2

than their associated branch

internodes and overlap each other. New

leaves,

tightly rolled along their length, emerge from the preceding leaf sheath, unrolling as they encounter the light of day.

The foliage leaves are not deciduous in most herbaceous bamboos, but they are deciduous in all woody bamboos. Unless in reaction to damaging cold, leaf fall does not occur all at once, but partially and gradually, so that bamboo is always evergreen. In some genera, such as Phyllostachys, individual leaves are replaced by branchlets and more leaves, making older culms denser with foliage. The duration and rate of replacement varies. In one study of Chusquea, foliage leaves remained for two or more years, but none remained longer than six years. The culm and branch leaves of some bamboos, including Phyllostachys, are immediately deciduous, abscising as soon as the internodes have completed their extension. As each succeeding internode of the rapidly growing culm completes its extension,

its leaf turns tan, falls back, and drops away

point at the culm, Even on a

fairly small bamboo,

from its last attachment

the culm leaves are quite large,

creating a significant spring and early summer leaf fall. In many bamboos,

however, including some in the genus Arundinaria, the

culm leaves persist, contributing to a tattered look as the culm leaf and its promi-

blade

pseudopetiole _

~

sheath

——}

fimbriae_

—

Figure 3. Foliage leaf.

_ ligule

auricle

Structure and Function

nent sheath weather. Sasa culm leaves persist, but the size of the foliage leaf blades so overwhelm

the size of the culm that the culm

leaves are not particularly

con-

spicuous. Semiarundinaria fastuosa rapidly begins to slough off its culm leaves, but they remain connected for a brief time at the center of the sheath’s base before finally abscising.

Other

bamboos,

such

as some

species of Chusquea,

burst

their

branches through a persistent culm leaf and its tightly attached sheath. For most woody bamboos, culm leaves offer a ready basis for identifying spe-

cies. Phyllostachys, among other genera, has highly distinctive culm leaf colors and patterns. Colors, including red, purple, yellow, brown, green, and tan, are patterned

in spots, stripes, and veins of various widths, combinations,

and gradua-

tions, often offering a dramatic display. The overt distinguishing characteristics of

color and pattern are helpful for field identification.

Other,

less overt leaf charac-

teristics also provide excellent keys for identifying bamboos. Such features include persistence of the culm

leaf; absence

or density

of surface hairs; posture of the

blade; shape and size of the auricles; presence and size of the fimbriae; shape and size of the ligule;

color, pattern, and surface tex-

ture of the sheath; and so on. Culm leaves vary from

the base to the tip. The culm

mid-culm

leaves from

most prominently display the distin-

guishing characteristics and are the most

repre-

sentative of the species.

Removal of the culm leaf stops growth of the corresponding internode. A dwarfing technique

for bamboo in the garden, and, more typically, for bonsai, calls for early removal of the culm leaf, thus compressing

the internodes,

increas-

ing branch density, and limiting height.

Blade On culm leaves, size of the blade relative to the sheath is not uniform

from nearly much

more

on a given plant, ranging

absent at the base of the culm to prominent

toward

the

top of the

culm. Near the culm tip, the blades develop into true foliage leaves that are as large as, or some-

times larger than, the blades of the foliage leaves on

the

rest of the plant.

Only

the foliage

leaf

e leaf of Phyllostachys decora culm The distinctiv

45

46

Chapter 2

blade consistently dominates its associated sheath and looks like a leaf in a conventional sense. Unlike culm leaf blades (except those near the tip of the culm), foliage leaf blades are attached to their sheath by a pseudopetiole,

giving the cus-

tomary appearance of leaves on stems.

The foliage leaf blades are the “leaves” we see when looking at a bamboo plant. They are the most complex and highly differentiated of the leaf blades on bamboo. The upper leaf surface is typically smooth and glossy, glistening when moistened. The lower surface has a dull, matte finish, caused by the numerous projections from the lips of the stomata. The underside is also sometimes covered with minute hairs. This surface prevents moisture from adhering to the leaf and

ensures that

the air passageways

remain

unblocked.

A leaf blade can be sub-

merged in water for an indefinite time. The upper surface will typically be wet, but the lower surface will essentially be dry, covered by innumerable air bubbles.

When applying insect or other foliar sprays to bamboo leaves, it is good to keep in mind that they will not normally adhere to the lower leaf surfaces. Insects that reside on the underside of the leaf may be subject to contact with the spray, but the

leaf surface will not, unless measures are taken to inhibit formation of the protective air pockets—measures which defeat the leaves’ natural protective system. All bamboos have parallel veins in the leaf blades. Transverse veins are present as well, and in some species, the transverse veins are prominent and visible, creating a rectangular vein pattern called tessellation. Tessellations are fewer, weaker, and less visible in tropical species, but generally very prominent and greater in number in hardy species. Although some species without tessellated leaf blades are hardy,

there is nevertheless a general correlation between

tessellation and cold

hardiness. Why this is so is subject to speculation. Bamboos that have a greater frequency of tessellation, and tessellation that is more

prominent,

are inherently

more capable of sap circulation within the leaf blade, which is likely a factor in cold

hardiness. culms.

Within given species, tessellation is greater on leaf blades from older

Bamboos

with

less prominent

tessellation also tend to have transverse

veins that are thin and S-shaped, whereas bamboos with more manifest tessellation tend to have transverse veins that are prominent, straighter.

protruding, and much

Leaf blade size and culm height or width are not directly correlated or, if anything, are sometimes inversely correlated. Mature culms of the largest hardy bamboo, Phyllostachys heterocycla {. pubescens, are up to 90 ft. (27 m) tall, with a diame-

ter of 7 in. (18 cm), yet they have among the smallest leaf blades of any woody bamboo. Conversely, Indocalamus tessellatus is typically no more than 4 ft. (1.2 m)

Structure and Function

tall with a culm diameter of barely 1 in. (1.25 cm), yet it has leaf blades that are 24 in. (60 cm) long by 4 in. (10 cm) wide, among the largest of any commonly cultivated bamboo. The largest bamboo

leaves belong to the New World genus New-

rolepis, up to 12 ft. (4m) long in some species, the largest known

leaves in the en-

tire grass family. Arborescent tropical bamboos generally have much

larger leaf

blades than arborescent hardy bamboos, but the general rule does not always hold. The foliage plumes of the delicate-leaved, tropical Thyrsostachys siamensis is a case in point. Young plants often have larger leaf blades than mature plants. A young plant’s

spindly culms are already out of proportion with the leaf blades, and the larger leaf blades only accentuate an ungainly stature. In one instance, some leaves of a 9 in. (23 cm)

measured

young Phyllostachys bambusoides of mine

by 1 % in. (4.4

cm), looking more like a large-leaved Sasa than a Phyllostachys. The delicate, finely shaped leaf blades of the small-leaved species define much of the look of bamboo in Asian art and poetry—delicate beauty, seen backlit and jewel-like, or as shadows painted on a white wall, or their sound, rustling, shimmering in the smallest breeze. The larger-leaved varieties create a bold, lush, trop-

ical effect. Together in the landscape, the small- and large-leaved species offer a splendid display of contrast and texture. It is said that the weight of the leaves in a grove is roughly equal to the weight

of the year’s new culms. The health and vigor of a grove is dependent on a large and healthy leaf canopy. When exposed

establishing a grove, preserving maximum

leaf area (except for bamboos

that require shade)

sun-

encourages the most

rapid growth. Employing this strategy may mean keeping aesthetically deficient culms for the first years of the grove. Such a strategy, however, does not mean that all culms should be preserved indefinitely.

A crowded grove keeps much of its fo-

liage in shade and diminishes vigor. Routine thinning ensures healthy culms and foliage canopies with good exposure to sunlight. Some species and forms have variegated leaf blades. Variegation is more unusual in larger species, but common among the dwarf and shrub species. In many dwarts, variegation intensity fades in sunlight and as the season progresses. Sasa veitchii exhibits a sort of pseudo-variegation.

the dark green

Toward

the end of their first season,

leaf blades wither at the margins, giving the appearance of beige

variegation rimming a dark green leaf. Under certain stress conditions, a plant

may

develop variegated

leaf blades

that subsequently return to solid green. When plants are grown from seed, the spontaneous appearance of variegation can be a source of excitement and confu-

47

sion.

You

may

think

you

find that the variegation

have discovered a new does not

repeat

and attractive cultivar, only

in succeeding

to

years or in plants propa-

gated from the original. Variegation should be observed over several seasons, and in plants vegetatively

propagated from the original, before firmly concluding that

it is a stable, variegated cultivar The foliage leaves of some tropical herbaceous bamboos are arrayed such that they which

have

a fernlike appearance.

the leaf blades change

A few exhibit

nocturnal

“sleep” movements,

shape with the coming of night.

in

The leaf blades of

Raddia fold upward along the culm, while those of Lithachne fold downward. This curious phenomenon begins at sunset and progresses over a four-hour period, reversing itself at dawn

ae

The variegated leaf blades of Sasaella masamuneana ‘Albostriata’.

Another style of variegation in Pleioblastus akebono.

Structure and Function

Sheath The sheaths tightly surround and protect the internodes as they lengthen. In the case of the rhizome, this occurs unseen, underground.

Although observable in

the growth of the branches, the role of the sheath is most visible and dramatic in

the growth of the culm. The inner surface of the sheath has a hard glossy finish, allowing the internode to elongate rapidly, while still retaining a tight, protective grip. The white powder visible on new culms of some bamboo substance

that helps the internodes extend

rapidly. The

species is a waxy

relatively unlignified,

emerging new culm is structurally weak and highly vulnerable to breakage and other damage. The culm leaf sheaths provide structural rigidity and a shield against impact, disease, and pest attack. The sheaths of some species are equipped with additional deterrents to protect the emerging culm. Gigantochloa apus and Guadua angustifolia, for example, are covered

with hairs that irritate the skin and the di-

gestive system.

Bamboo and

may

sheaths

are sometimes

be photosynthetic,

though

green this is

hardly their primary role. The ridges that run lengthwise on the outer surface of the sheath

are caused by the vascular strands that eventually extend

into the leaf blade, providing

the vascular connection with the rest of the plant.

Ligule The ligule, or “little tongue,” extends upward

from the tip of the sheath proper. Depending on the species, the ligule can be prominent or inconspicuous in size, and it may bear cilia or bristly hairs.

The ligule helps keep mois-

ture away from the newly forming culms and branches and prevents moisture from runRight: Two culm leaves from a new Phyllostachys vivax shoot. The sheath comprises nearly the entire leaf. The blade at the tip is barely noticeable. The top culm leaf shows the exterior of the sheath. The culm leaf underneath shows the hard glossy finish

of the sheath’s interior surface.

49

50

Chapter

2

ning down

the culm or branch and collecting at the node. The woody

bamboos,

unlike herbaceous bamboos, also have an outer ligule, but it is always much smaller than the inner ligule and is almost always scarcely visible.

Auricle The auricles, or “ears,” are located at the upper part of the sheath, on both sides of the blade. Depending on the species, they may be prominent

or entirely lacking,

and present on both sides of the sheath or only one side. Auricles may be deciduous with age and are best observed on young leaves. Regardless of species, auricles are entirely absent from rhizome leaves or bracts.

Fimbriae Fimbriae, also called oral setae, are the bristly, fringelike hairs that extend from the margins of the auricles. They may be either prominent or lacking, depending on the species. Although usually associated with the auricles, they may be present even when

the auricles are

absent, extending from the uppermost

margins of the

sheath.

Flowers and Flowering Grass flowers are seldom showy.

nial grasses, bamboo

As with most peren-

seed set is often poor or infre-

quent, making vegetative reproduction an important means of propagation. Largely because traditional tax-

onomy was centered on the flowering parts of plants, and the inflorescences of bamboos

are evolutionarily

quite primitive, bamboos were thought to be the most ancient grasses. With modern however,

it is now known

molecular techniques,

that bamboos are not the

most ancient of grasses, even though

their inflores-

cences retain ancient ancestral features (Clark

Like most grasses, bamboos

1997a).

are generally wind

Left: A new Phyllostachys nigra shoot showing the pronounced auricles and fimbriae. The crinkly leaf blades of the culm leaves cluster at the tip of the shoot.

Structure and Function

pollinated, and the flowers are structured accordingly. Petals are absent or highly reduced

to scales called lodicules. Bamboo

flowers lack nectaries for producing

insect-attracting sugary secretions, but pollen is produced abundantly, and stigmas are feathery to readily catch the pollen in the wind.

Some

tropical herbaceous

bamboos that inhabit the rainforest floor may be exceptions to the wind-pollination rule. On the rainforest floor, breezes are all but absent, but these herbaceous bamboos are routinely visited by insects and are likely pollinated by them.

Bamboo

flowering is the subject of much mystery, controversy, and confu-

sion. Although

a few woody

bamboo

species flower continuously or annually,

most flower rarely. Many species remain in a vegetative growth period for decades without

flowering. Some species have never been known

to flower, except for a

few isolated plants. In well more than a century of observation, Bambusa vulgaris has never had a general flowering period. The few isolated B. vulgaris plants that have flowered failed to produce viable seed, yet the species is vigorous and apparently undiminished by the lack of genetic diversity. Flowering is said to occur in great cycles, unique to each species, frequently

spanning many decades, or more than a century in some instances. The cycles are said to occur simultaneously throughout the world, independent of local climate

and growing conditions. Species of Sasa, for example, are purported to flower in roughly 60-year cycles, although

more. Kawamura’s

some sources indicate a cycle of 100 years or

1927 study, using local records and folklore, traced the flow-

ering of Japanese timber bamboo, Phyllostachys bambusoides, back to 800 A.D. The study concluded that P. bambusoides has a flowering cycle of 120 years, predicting that the next gregarious flowering of the species would occur in 1960, 120 years after the last great flowering in 1840. The prediction proved largely true, when a wave of flowering spread from northern to southern Japan from

1959 into the

1970s, and the species flowered as well in America during roughly that same period. In spite of such

dramatic

examples,

evidence

of flowering

cycles

is largely

anecdotal in nature, absent empirical rigor, and subject to wide variation. It is true that many bamboos of the same species have been observed to flower gregariously throughout the world within a several-year period, after decades of no flow-

ering. Yet, not all plants of a species flower at once. It is more likely that vegetatively propagated cohorts with the same genetic source, and of the same age, are more likely to experience simultaneous flowering. Assuming that this is the case, then over time, particularly with human intervention, the flowering interval may spread over an increasingly extended time span, to the point that flowering peri-

51

52

Chapter 2 ods may begin overlapping. For example, a bamboo plant or grove may flower and produce seed over a period of several years. The earliest plants from the flowering will be several years older (and potentially flower sooner) than the plants

from the very end of the flowering cycle, and even more so if the seed at the end of the flowering cycle is “saved” and germination is delayed. If the process is repeated at the next

(now extended)

flowering cycle, the span

of flowering and

seeding increases yet again. Combine this with the free-flowing exchange of seeds and plants among growers throughout the world, the diminished instances of iso-

lated and undisturbed natural stands of bamboo, and the likely existence of multiple cohorts, the predictability of flowering cycles diminishes even further. Indeed, every year, Phyllostachys heterocycla f. pubescens is in flower somewhere

in China.

Nevertheless, this does not compromise the assertion that plants of the same age from the same cohort will flower at extended intervals and at the same time. Traditionally, we have attempted

to track species in order to formulate some sort of

understanding of flowering cycles. More appropriately, perhaps, we should be tracking cohorts, or seedlings of the same age from the same plant, or even more accurately (but even

more impractical), we might track vegetatively propagated

plants from the same seedling, ruling out genetic variation among seedlings. Given the extended length of bamboo flowering cycles, sometimes exceeding a century, the general practicality and accuracy of such measures would be rather dubious. The

mechanism

or mechanisms

that

trigger flowering

remain

largely

un-

known. Various hypotheses attempting to explain the synchronized and extended flowering cycles include predator satiation, parental competition, drought, sunspots, earthquakes, and other environmental

factors. In his paper, “Why Bam-

boos Wait So Long to Flower,” Daniel H. Janzen

(1976) exhaustively studies re-

ports of bamboo flowering dating back more than a millennium, and he offers the

hypothesis of predator satiation. He theorizes that seed is produced in such abundance that it exceeds the ability of seed predators to consume or destroy all the seed,

thus

leaving

enough

viable seed

to become

the succeeding

generation.

Janzen argues that the long vegetative period before flowering is necessary for the plant to accumulate sufficient reserves for the massive flowering and seed pro-

duction. He and others estimate that the recovery and rebuilding reserves for the next cycle would take some

15 years. If this is the case, the typically more ex-

tended flowering cycles are not explained pothes

without

additional supporting

hy-

such as the suggestion that doublings of the internal clock might arise

from mutation or changes in the chromosome count. Neither the predator satiation hypothesis nor others have gained broad acceptance. Clearly, when

it comes

Structure and Function

to explaining bamboo flowering, we are rich in arcane hypotheses and impoverished in knowledge. Apart from the larger picture of flowering cycles, chemical triggers and associations with flowering are also the subject of study. When flowering is induced in vitro, cytokinins are present. Cytokinins are growth-regulating substances associated with delayed senescence, promotion of cell division, breaking dormancy, and

flowering. Their role and the reasons for their association with flowering in bamboo is yet to be determined. One study found that flowering was associated with

oxidation stress and the presence of hydrogen peroxide, superoxide, and other active oxygen species (AOS). AOS can damage biological molecules such as DNA, proteins, and

membranes

and cause cell death. The weakened,

brittle culms of

flowering bamboo

may be related to AOS. This study suggests that research on

bamboo

has been

flowering

hindered

by emphasizing

the genetic component

rather than physiology, postulating that the flowering of Fargesia murielae in Europe in 1994,

1995, and

1996 was linked to hot summers and high ozone con-

centrations, generating oxidative stress and flowering in bamboos

(Gielis et al.

1997). However, F. murielae flowered in other parts of the world during that same time period, under widely varying environmental conditions, suggesting that oxidative stress may exacerbate a preexisting disposition toward flowering, but is not itself the causal element.

As more

becomes

known

about

the physiological

associations with flowering, the actual causal factors may reveal themselves more clearly. Various environmental factors can influence flowering. In India, for example, Dendrocalamus strictus flowers erratically in drier regions, but more periodically in wetter regions. Apart from “normal” flowering cycles, stress can bring on flowering. When a grove has been damaged by fire, the rhizomes of pachymorph

bamboos have been known to initiate flowering. Drought and winter damage can also bring on flowering, although success in attempting to induce flowering by introducing these factors is far from certain. Winter damage to bamboos of the genus Phyllostachys, for example, does not typically elicit a flowering reaction. Oxidative stress exacerbated by high light intensity and drought may contribute to the onset and rapidity of flowering. Conversely, the absence of stress may delay or fully circumvent flowering. Providing ample water and nitrogen fer-

tilizer may prevent, delay, or minimize flowering, though none of this is certain. If flowering has begun but is not desired, immediately remove the culms that have begun to flower, generously apply nitrogen fertilizer, and water heavily. Bamboo groves in the rich soils of China’s Zhejiang Province have reportedly maintained

53

54

Chapter 2

vigorous growth for more than two centuries by controlling flowering behavior (Wang and Shen

1987).

Befitting the mysterious nature of bamboo flowering, it is little surprise that seemingly contradictory conditions are associated with flowering. Stress is generally thought to contribute to the onset or rapidity of inflorescence, but disturbance

or stress may also disrupt a bamboo’s ability to accumulate sufficient energy reserves to flower. When Bashania faberi gregariously flowered in Wolong, China, in 1984, some patches did not flower. Those patches were not random,

but were

concentrated at elevations above roughly 10,000 ft. (3000 m)—or below roughly 10,000 ft. (3000 m) in clearcuts, or on steep north-facing slopes. This suggests that bamboo plants that have been stressed in a way that prevents them from accumulating adequate energy reserves may have retarded flowering.

Except for those species that flower yearly or are in continuous flower, most bamboos with pachymorph ering. Some

rhizome systems are monocarpic and die after flow-

plants, such as beeches,

flower and

fruit heavily at intervals, and

other plants, such as many grasses, die after flowering, but a prolonged vegetative period lasting years or decades, followed by flowering and death, is a distinctive and peculiar characteristic of bamboo.

For monocarpic bamboos,

the viability of

the seed and success of the new seedlings are critical for ongoing survival. Since the mother plant will die, seed offers the only option for continuation.

Most bamboos with leptomorph rhizome systems are typically severely weakened from flowering but eventually recover, though a decade may pass before a large, mature grove is fully restored to its former stature. Mortality is more likely when growing conditions are less than optimal and when there is a heavy seed set from the flowers. Gregarious flowering and seed set consumes all the energy reserves stored in the parenchyma cells of the culm and rhizome. The culms die and become brittle, bending or breaking easily. Sometimes it seems that there are more exceptions to the flowering rule than

followers of the rule—whatever the rule may be. In contrast the genus’s normal flowering pattern, at least one clone of Phyllostachys elegans has flowered sporadically, every year, for more than a decade, while continuing to grow with moder-

ate vigor. Bamboo nurseryman Ned Jaquith reports acquiring divisions of flowering P. vivax and P. bambusoides to conduct

hybridizing experiments,

only to have

both cease flowering and regain normal vegetative vigor. Jaquith also reports that a grove of P. vivax began to flower after he provided it with ample water and fertilizer. The grove continued to flower gregariously for about a decade before even-

has completed its monocarpic flowering and is now all but dead.

56

Chapter 2

tually dying. During that time, there were two periods of new culm growth with no flowers, but flowering returned the following season. In many species, reduced plant vigor, early shooting, deformed growth, and weak culms and branches mark an impending period of gregarious flowering. Occasionally, a single culm or branch may flower in response to stress. Such flowering does not necessarily indicate a period of gregarious flowering. The bamboo may return to its vegetative growth cycle without any further flowering. From a commercial and aesthetic standpoint, gregarious flowering can be devastating. In general, neither a commercial grower nor a gardener would want to rely ona

single species or, at minimum,

on the same vegetative clone of the same

species for risk of losing an entire grove to flowering. In China, Phyllostachys heterocycla f. pubescens overwhelmingly

dominates

the vast commercially vital bam-

boo forests, but the plants are by no means all of the same vegetative clone. Every year, some P. heterocycla f. pubescens is flowering somewhere in China, but given the infrequency of flowering, and the great clonal diversity, the flowering bamboos are only a tiny fraction of the total bamboo forest. A grower intending to focus on a single species should ensure that the groves are made up of diverse clones. Obtaining plants started from seed, and from flowerings that occur years apart, is one way to ensure diversity. In the United States and Europe, many plants originate from

very few clones, so diversity is inherently less likely. In addition to the impact on commercial

production and the health of the

grove itself, the generalized flowering of a grove made up of a single species can have significant ramifications on the health and well being of human communities. For cultures that rely on a bamboo grove for shelter, tools, and food, the death of the grove from flowering can be devastating.

The importance of clonal diversity was graphically demonstrated in Thailand in the 1990s. In the early 1900s, Dendrocalamus asper was brought from China and extensively vegetatively propagated. By the early 1990s, some 28 factories annually

produced 68,000 tons of bamboo

shoots. In 1994 to 1995, D. asper flowered gregar-

iously in Thailand, devastating the industry. Some 94,000 acres (38,000 hectares) of

D. asper were eliminated from production, and more than 35,000 farmers lost their livelihood (Muller 1996b). In all, some 70 percent of Thai D. asper flowered.

Diversity of species or clones is critical to the avoidance of a precipitous devastation such as befell Thailand. At least five other known clones of Dendrocalamus asper did not flower during this same period. A mixture of clones would have avoided disaster. Diversity would mean only a temporary reduction in productivity as a portion of the plants flowered, rather than the devastation of an industry.

Structure and Function

Dendrocalamus asper is said to have a flowering cycle of more than a hundred years, and plants generated

again for more than

from seed of the recent flowering should not flower

100 years. From one point of view, these plants would be ideal for establishing a plantation, but a plantation or forest consisting of mixed clones on differing flowering cycles may be the better prospect for ongoing stabil-

ity. Adding another twist to this particular example, there is some indication that

the Indonesian clones of D. asper may not undergo a gregarious flowering cycle. If true, a selection of these clones might be the best choice of all. Flowering is both a threat and an opportunity. The threat is the death and total loss of the plant, or grove, or forest. The threat may also be the loss of a unique cultivar that may not be readily reproduced from seed. When

Phyllostachys

bambusoides {. castillonis gregariously flowered, the form virtually disappeared from America and Europe. Occasionally, an opportunity arises when a sport from a

stressed flowering bamboo produces a new cultivar. A highly variegated P. bambusoides was discovered as a sport growing from a flowered-out P. bambusoides f. castillonis that was in demise. The original P. bambusoides ‘Kawadana’ was a sport from a flowering P. bambusoides. The P. bambusoides ‘Kawadana’ currently in circulation

in the United States originated in England, as a sport from a recovering P. bambusoides f. castillonis that had flowered. Stressed and recovering bamboos may occasionally produce sports that become new and interesting cultivars or replicate existing cultivars. So what should one do when bamboo

flowers? Try to save the existing plant,

particularly if it is a bamboo that is capable of recovering after a gregarious flowering—typically leptomorph bamboos. If the bamboo is a cultivar, variety, or form

that may not readily reproduce from seed, saving the flowering plant is all the more important. Also, be on the alert for sports that may arise from the stressed condition. Secondly, harvest the seed and, if possible, grow the seed in a controlled

environment rather than in the ground under the flowering plant, in order to ensure maximum

survival.

Various practices can be employed to save bamboo once it has begun to flower, but there are no guaranteed methods.

A common

practice calls for cutting the

flowering culms to the ground and fertilizing heavily. A. H. Lawson, former head

gardener of the gardens at Pitt White in southern England, recommends against this practice, and instead suggests lessening the strain on the plant by removing the flower spikes as soon as they appear, much as one would remove the plumes from a grass stem. According to Lawson, this method allows the foliage leaves to continue to produce food stores for the plant, prolonging its life. Others argue that

Dil

1 Ley

Sade:

ix@

sé

This clump of Otatea acuminata ssp. aztecorum at Quail Botanical Gardens has flowered and set seed. Although some of the seed has been harvested to grow in a controlled environment, the rest has been left alone as in the wild. Some of the seeds have fallen to the ground, germinated, and generated new seedlings, as seen on the lower left

Structure and Function

this method alone has little effect, and advocate cutting off any culms that are flowering, then dividing the plant into smaller plants by cutting the rhizomes with an ax or specialized rhizome cutting tool, followed by fertilizing and watering. Any new culms that start to flower are removed as well. Results vary. Even though

all the culms may enough

be removed,

and all the new culms as well if they flower,

foliage may have been on the plant long enough

to augment

the energy

reserves of the rhizomes, permitting yet another new set of culms. These may be exceptionally spindly and weak, but eventually, if enough

culms remain

that do

not flower, the bamboo can be saved. If just one plant can be saved, it can be vegetatively propagated, and the existing generation can be restored.

When a bamboo gregariously flowers, it is in a highly stressed and weakened condition. As a general rule of thumb, reduce stress to the plant as much as possible. Provide ample water and nutrients (but do not compound the stress by waterlogging the soil or overfertilizing) and shelter the plant from dehydration and climate

extremes.

Seeds Typical of most grasses, bamboos generally produce seed grains (caryopses), but there are variations. In Schizostachyum, the caryopsis has a hard, thick pericarp that is easily separated from the seed. Some tropical bamboos, such as species of Melocanna, produce a large fleshy fruit. Dinochloa is a berrylike fruit, with a thick fleshy

pericarp enclosing a large embryo. In general, fruits are not regarded as a key element in taxonomy, but it is an important identifying factor for Dinochloa. The size of the seed also varies widely. Bambusa bambos yields approximately

41,000

seeds per pound

12,000 seeds per pound ends of the spectrum,

(90,000 seeds per kilogram),

B. tu/lda approximately

(26,000 seeds per kilogram), and toward

Dendrocalamus longispathus about

the extreme

68,000 seeds per pound

(150,000 seeds per kilogram) versus Melocanna bambusoides at a mere 32 seeds per pound (70 seeds per kilogram) (Rao and Zamora

1996).

Although the generalized flowering of a grove can create great difficulties for cultures that rely on the grove for shelter, food, and other resources, the bamboo seed can also be a major windfall, such as for the grain produced by those species with abundant and large seed. Historical accounts from India tell of bamboo seed providing relief from famine during the 19th century. In Orissa, in 1812, a general flowering of bamboo produced an abundance of seeds that were cooked and eaten like rice. In 1864, an estimated 50,000 people made their way to the Soopa jungles

a9:

60

Chapter

2

to collect seed. After about them

through

two weeks of collecting, they left with enough

the monsoon

India, records show

season,

as well as extra

to sell. In another

to last part of

that, in 1866, abundant bamboo seed sold on the market for

about 20 percent less than the price of rice. Similar accounts from China and harvests.

Japan tell of hunger relief and abundant seed

In 1843, bamboos surrounding the town of Takayama

for a distance of

many miles flowered and produced an abundant crop of large seed. If the historical accounts can be believed, more

than a million bushels of bamboo seed were har-

vested

in various ways,

for food and consumed

dumplings,

including ground

noodles, and gruel. A kind of sake produced

into flour for

from the seed was said to

taste a bit sharp, but otherwise similarto sake made from rice. The nutritional qualities of bamboo Japan, the

bamboo seed

Bamboo neath

seed are somewhat

superior

to rice and wheat

(Janzen

has been called natural rice, bamboo rice, and

can produce extraordinary

the mother plant can be as much

1976).

bamboo corn.

quantities of seed. The fallen seed beas 5 to 6 in. (13 to 15 cm)

deep. In one

study, a 40 square yard (33 sq. m) clump of Dendrocalamus strictus produced (145 kg) of seed. Although

most

bamboo

In

320 lb.

seed is relatively small, Melocanna bac-

Bamboo seeds. Clockwise from the upper left, Bambusa heterocycla f. pubescens, and Dendrocalamus strictus

tulda, Fargesia murielae, Phyllostachys

Structure and Function

cifera, a bamboo native to India, Pakistan, and Bangladesh, produces a fruit the size of a pear. In 1867, a surveyor reported that, over a 6000 square mile (16,000 sq.

km) area, M. baccifera plants dropped their fruit so thickly that his surveying instruments were damaged,

forcing him to stop work.

In spite of these remarkable occurrences, relatively few bamboo species pro-

duce abundant edible seed. Some species produce very few seeds, and they may be too small to bother harvesting except in desperate situations. In the same historical recounting of Takayama’s large seed harvest, the seed of hachiku nigra var. henonis), madake

(P. bambusoides), and medake

(Phyllostachys

(Pleioblastus simonii) are

described as too small and not sufficiently abundant to harvest for food. Bamboo seed is subject to damage and decimation from insects, birds, and rodents. Just as bamboo seed can be a windfall source of food for humans, so too it is for rats and other rodents. In Brazil, Merostachys multiramea flowers and sets massive quantities of seed three to four times a century. The seeds are sometimes baked into breads or used as feed for poultry, but the great abundance of seed also engenders a dramatic increase in the local rodent population and a corresponding increase in poisonous snakes that feed on the rodents—neither of which are par-

ticularly beneficial to human inhabitants. Seeds of tropical pachymorph

bamboos such as Bambusa and Dendrocalamus

typically ripen in two to four weeks. Temperate leptomorph bamboos such as P/ry/lostachys require 7 to 10 weeks for the seed to ripen. The ripe seeds are then easily

released and drop to the ground. Most bamboo seed is not widely dispersed and is usually nota

factor in the expansion of bamboo’s range. Seedlings generally arise

in very close proximately to the mother clump, though there are occasional exceptions. The large, fleshy fruits of Me/ocanna baccifera can roll downhill and establish new colonies at more distant locations.

Rhizome Morphology and Clump Habit For many, the following discussions of rhizome systems and clump habit will be more than you may want—and less. After well more than a century, and many attempts at systematically describing rhizome systems and clump habits, the terminology (and the underlying understanding) is still not entirely satisfactory. The of a muddle for scientist, grower, and hobbyist alike. Traditionally, bamboos have been loosely divided into two broad types according to the visible spatial relationships of their culms: caespitose (tightly subject remains somewhat

grouped or clumped) and diffuse (spread about or scattered). More popularly,

61

62

Chapter

2

these two types are termed clumping and running, or clumpers and runners. The two types are associated (rather imprecisely, as we shall see) with the rhizome form as well as with the branching habit of the rhizomes. The two growth habits illustrate alternate survival strategies. Clumping bamboos spread slowly, but present an impenetrable phalanx against invasive growth.

Running

bamboos

present an alternate strategy, being the e' sence of invasive

growth. They spread rapidly into new territory, finding gaps in the forest canopy, penetrating the root systems of existing plants with sharp rhizome tips, using the energy

stores and

photosynthetic activity from

the established portions of the

bamboo plant to rapidly send new culms above the competing foliage, then building an impenetrable mat of rhizomes. Because this book is intended primarily for an audience of gardeners, growers, and landscapers, the terms clumping and running are sometimes given license, as

it is the customary vernacular of bamboo users and enthusiasts, myself included. As we shall see, however, the terminology is reasonably practical within a limited context, but imprecise. As gardeners, growers, and landscapers, we are concerned with the way bamboo extends its territory. Its characteristics in this regard determine what we need to do to control its spread, or increase its spread, or how it will

fit and interact with the other plants and features in the landscape. For these purposes, the terms clumping and running serve us sufficiently well, particularly those of us who live in temperate rather than tropical or subtropical climates and thus are not confronted may also want

by as many

to concern

of the exceptions to the rule. However,

ourselves with propagation

we

or with a greater under-

standingof structure, function, and habit, or we may want to contend with one of the many exceptions. For these purposes, greater precision is warranted. We will explore this more precise terminology and employ it in this book as required.

Terminology In the sections that

follow,

the use and

misuse

of terminology

will be further

detailed, but as a point of reference, the terms and what they describe can be summarized

as follows:

Rhizome morphology: pachymorph, leptomorph, amphimorph Branching habit: sympodial, monopodial, amphipodial Culm and clump spacing (formal terminology): caespitose, diffuse, pluricaespitose

Culm and clump spacing (informal terminology): clumping, running

Structure and Function

Various terminologies are encountered in bamboo literature. Although the terms sympodial and determinate properly refer to branching habit rather than rhizome morphology, they are often encountered in the literature as referential to

rhizome morphology. In this (inauthentic) context, they are broadly synonymous with the term pachymorph. Similarly, in the literature, the terms monopodial and

indeterminate are broadly synonymous with the term leptomorph. Because of variations in rhizome habit and culm initiation within the broad categorizations of clumpers and runners, terminology satisfying the more precise requirements of science has been troublesome. As a practical observation and inclination, we may note distinctive clump habits of various bamboos and look to draw distinctions on that basis. That is, we may note that the culms of different bamboos have distinctly different spatial relationships, some caespitose (tightly grouped or clumped), some diffuse (widely spaced), and perhaps some pluricaespitose (multiple groups or clumps with wide spaces between them).

Making

just

these sorts of observations, Riviere and Riviére, in 1879, were perhaps the first to

publish the distinctive growth behaviors, noting that Gigantochloa and Phyllostachys exhibited distinctly different growth habits, which they identified as “caespitose” and “spreading.” Both taxonomically and otherwise, rhizome

had largely been

ignored

until

the morphology and 1925, when

physiology

F. A. McClure

of the

published a

proposal for the terms sympodial and monopodial to describe the branching habit of the rhizome rather than the clumping habit of the plant. In sympodial branch-

ing, each succeeding branch, or axis, becomes dominant. In the context of rhizomes, each new rhizome turns upward and becomes a culm. In monopodial branching, a single, dominant stem, or axis, gives rise to secondary branches, or axes. In the context of rhizomes, each rhizome runs laterally, usually without turning upward to become a culm. This rhizome gives rise to secondary axes that either turn upward to become culms, or constitute new laterally running rhizomes that will, in turn, give rise to secondary axes of their own. Although the rhizome branching types often correlate somewhat

with the spatial relationships of the

culms—sympodial with caespitose (clumping) and monopodial with diffuse—the correlationis far from perfect, hence McClure’s choice and definition of more specific and less ambiguous terminology for the rhizome. In 1948, the Chinese botanist P. C. Keng promulgated an additional term, am-

phipodial, to describe bamboos, such as Shibataea kumasaca, that have monopodial rhizome systems but are also capable of generating new culms by tillering from the base of existing culms, in the manner of a sympodial system. The term itself, as

63

64

Chapter

2

originally conceived, suggests that a single species may have both rhizome types, but it is questionable whether the base of the tillering culms should be considered

rhizomes at all, as they are not generally thickened, nor do they have the initial horizontal or subhorizontal growth habit characteristic of sympodial rhizomes. It

can be argued that, once again, although in a more subtle fashion, the description of branching, clump habits, and rhizome forms have been intermingled and mud-

dled. However, if the term amphipodial is applied more narrowly and authentically, to refer only to branching habit, then it is both useful and valid. Bamboos such as S. kumasaca have rhizome systems with monopodial branching and tiller-

ing culms that exhibit sympodial branching. Since both branching patterns are present, the species can be said to have amphipodial branching. Over time, the use, misuse, and subsequent confusion of the terms sympodial, monopodial, and amphipodial rendered them increasingly ambiguous, sometimes

referring to the spacing and manner of culm initiation rather than to the morphology of the rhizome.

In 1966, to rectify the ambiguous terminology, McClure

proposed the terms pachymorph

and leptomorph to characterize the two basic

types of rhizome morphologies. In this context, although Shibataea kumasaca exhibits amphipodial branching, its rhizome system is strictly leptomorph. Most authorities have generally adopted the terms pachymorph

and lepto-

morph to describe rhizome types, although some still regard the terms as synonymous and superfluous, preferring the earlier terms sympodial and monopodial. This point of view, however, merely plunges us back into the muddle. Separating branching habit (sympodial,

monopodial, and amphipodial)

from rhizome mor-

phology

leptomorph)

in clarity. With

(pachymorph

and

is a step forward

the

change in terminology and concept to pachymorph

and leptomorph, the term

amphimorph

replacement for amphipo-

is sometimes employed as a convenient

dial, but as such, it is typically misapplied. Authentically, the term amphimorph indicates the presence of both rhizome types: pachymorph are there species that have amphimorph

and leptomorph.

rhizome systems—that

So,

is, both pachy-

morph and leptomorph rhizomes? Although this is also somewhat a matter of debate, in part because of a misapplication of the terms, the answer is “yes,” but the

occurrences are rare. Although there are probably more, the only three species with confirmed amphimorph rhizome systems are from the New World. They are Aulonemia fulgor, Chusquea fendleri, and C. scandens (Judziewicz et al. 1999).

Confusion continues because of the persistent inclination to use the same terms to describe several different but interrelated aspects: branching habit, rhizome type, and culm spacing. With respect to culm spacing and clump habit, bam-

Structure and Function

boos with leptomorph

rhizomes are usually

“running bamboos”

with widely

spaced culms. In temperate climates, bamboos that have pachymorph

rhizomes

are typically “clumping bamboos” with closely spaced culms. Yet, although this is usually the case, it is also sometimes far from true. Confusion is not just confined

to the casual gardener. In a recent study, researchers believed they had failed in their attempt

to demonstrate a difference in the DNA

and monopodial some bamboos

of genera

with sympodial

rhizomes. In their study, the researchers had incorrectly grouped with

pachymorph

including Melocanna and

rhizome

systems

(and sympodial

branching),

Yushania, with bamboos that have leptomorph rhizome

systems (and monopodial branching). Although Melocanna and Yushania have pachymorph rhizomes, the rhizomes have very long necks and, thus, diffuse culm spacing. The researchers had confused culm spacing and clump habit with rhizome type (and the rhizome type was also incorrectly characterized by terms that should have been used to describe branching habit rather than rhizome morphology). In this instance, the ambiguities in terminology led to erroneous conclusions.

Rhizome morphology Pachymorph systems. A pachymorph rhizome always turns upward and becomes a culm.

It is nearly always curved and, at its maximum

width,

is slightly

thicker than the aboveground culm it becomes. Rhizome nodes are not prominent. The internodes are wider than they are long and usually solid. New rhizomes emerge

from

lateral buds on an existing rhizome.

As with the original rhizome,

these new rhizomes always turn upward and become culms. The neck of the rhizome can be either long or short. Most pachymorph bamboos are tender plants that thrive in tropical or semitropical environments and tolerate little or no frost. In America, they typically initiate new shoots and culm growth in the summer or fall, sometimes triggered by a period of heavy rain or moisture following a period of relative dryness. Some pachymorph species, are adapted

bamboos, such as a number of the New World Chusquea

to temperate climates. Although

pachymorph

bamboos are

generally associated with tropical and semitropical environments, some of the world’s hardiest bamboos have pachymorph

rhizomes. Fargesia nitida and F. murie-

lae, for example, both delicate montane bamboos with pachymorph rhizomes, are extraordinarily cold hardy. These bamboos are shrublike rather than arborescent. With rare exception, arborescent bamboos with pachymorph rhizome systems are tropical or semitropical.

65

66

Chapter 2

Leptomorph systems. The structure and growth habit of a leptomorph rhizome differs from a pachymorph

rhizome. Although a leptomorph

rhizome can

turn upward and become a culm, it most typically runs laterally without becoming a culm. A leptomorph rhizome is usually hollow and smaller in diameter than the culms that originate from it. The rhizome neck is always short. Internodes are longer than wide. Nodes are sometimes prominent. Buds are arranged horizontally, and most remain dormant, but those that germinate may produce either culms or new rhizomes.

Most researchers regard leptomorph rhizomes as a later evolutionary development, although this is subject to debate. In one scenario, the leptomorph rhizome

may

have

evolved

through

prostration

of the

culm, subsequently becoming more specialized and developing its own season of growth. Most

leptomorph

bamboos

are frost-hardy

plants

that thrive in temperate environments with warm sum-

mers and distinct winters that provide a period of dormancy.

Some species are able to tolerate temperatures

below 0°F (-18°C) without sustaining damage. In North America, leptomorph bamboos thrive in the temperate

climates of the coastal states and provinces, although they have proven sufficiently hardy to be grown in the interior of the continent. Leptomorph

rhizomes typi-

cally grow during late summer and fall. New shoots and

culm growth typically occurs in early spring through early summer

(some, such as species of Chimonobam-

busa, are exceptions and

initiate shoots in the fall). Ris-

ing temperatures rather than moisture is typically a factor in shoot initiation. Leptomorph size

from

the

smallest

of

the

bamboos

woody

range in

bamboos,

the

groundcovers and shrubs such as Pleioblastus pygmaeus var. distichus, to the giant arborescent

species such as

Phyllostachys heterocycla f. pubescens.

rhizome ~ Figure 4. Pachymorph rhizome system.

Amphimorph systems. Bamboos with amphimorph rhizomes are rare. Their rhizome systems include both pachymorph and leptomorph rhizomes. So far, amphi-

morph

rhizome systems have been confirmed in only

Structure and

three species, Aulonemia fulgor, Chusquea fendleri, and C. scandens. Bamboos with tillering culms, such as Shibataea kumasaca, have amphipodial branching—rhizomes with monopodial branching—but

branching,

and

tillering culms that exhibit sympodial

they do not have amphimorph

rhizome systems. The rhizomes

are strictly leptomorph.

Culm spacing and clump habit A system that separately describes culm and clump habit in conjunction with rhi-

zome form is now in place at Britain’s Royal Botanic Gardens, Kew. It is employed in conjunction with Kew’s World Grasses Database and used for the morphologi-

Figure 5. Leptomorph rhizome system.

Function

67

68

Chapter 2

cal and cladistic analyses conducted at Kew. As with any and all such systems, there are limitations and inevitable ambiguities, but this system makes another positive step in effectively describing rhizome morphology and culm and clump spacing.

Culm and clump terminology addresses the spacing of culms and clumps, independent of the rhizome morphology. Bamboos with pachymorph rhizomes and bamboos with leptomorph rhizomes can have the same clump habit. Conversely,

bamboos with the same rhizome morphology can have different clump habits. For example, Guadua angustifolia has pachymorph

rhizomes and Phyllostachys vivax

has leptomorph rhizomes, but the culms of both are diffuse (widely spaced). Bambusa multiplex has pachymorph

rhizomes like G. angustifolia, but its culms are cae-

spitose (tightly spaced). Environmental conditions can play a role in the clump habit. In general, if heat, light, and moisture approximate the ideal for a species, growth will be more vigorous and diffusion more exaggerated. Diffuse. The term diffuse refers to culms that are widely spaced, arising singly rather than in groups. This growth habit is commonly synonymous

with “run-

ning bamboos.” It is also commonly, but erroneously, associated solely with leptomorph bamboos. In the United States and other temperate climates where bamboo is grown, most bamboos with a diffuse habit have leptomorph rhizomes—but not all. Some

temperate-climate

Chusquea,

for example,

have pachymorph

rhi-

zomes but a diffuse habit. Some species of Guadua, a genus of the New World tropics with pachymorph

rhizomes, can have exceptionally long rhizome necks that

extend 20 ft. (6 m) or more before turning upward

a Mexican bamboo with pachymorph necks, and

new

to form a culm.

Olmeca reflexa,

rhizomes, has greatly elongated rhizome

culms can be spaced as much

as 26 ft. (8 m)

apart. Both

Guadua

and Olmeca have exceptionally diffuse culm habits that easily outrun most leptomorph bamboos. Caespitose.

Caespitose culms are spaced closely together in a tight clump.

This growth habit is sometimes termed unicaespitose and is commonly synonymous with “clumping bamboos.” Although bamboo species with leptomorph rhizomes can display this habit as seedlings, when

first planted, or when

grown

in

problematic conditions, such as heavy shade or in cold summer climates, a normally vigorous leptomorph bamboo does not have a caespitose clump habit. Within the context of a normally vigorous bamboo, only pachymorph bamboos

Structure and Function

with short rhizome necks have caespitose clump habits. Some species of Bambusa and Dendrocalamus are examples of pachymorph

bamboos with short rhizome

necks and a caespitose clump habit. Pluricaespitose. In a pluricaespitose clump habit, culms arise in dispersed clumps. This clump habit is sometimes termed multicaespitose or compound-caespitose. Because new culms can appear far from existing culms, this growth habit is also commonly associated with “running bamboos.” Some species with pachymorph rhizomes that have a combination of short and long rhizome necks display

this culm and clump habit. Yushania, for example, has rhizomes of varying neck lengths. New rhizomes arising from the lower buds closer to the rhizome neck have long rhizome necks. New rhizomes arising from the upper buds closer to the culm have shorter rhizome necks. In succeeding years, this growth habit produces

widely dispersed small clumps. Some species with leptomorph

rhizomes and tillering culms also have this

culm and clump habit. The culms arise spaced widely apart along the leptomorph rhizome, but new culms tiller off the base of existing culms, forming small clumps spaced widely apart from other small clumps. Bamboos with leptomorph rhizomes and tillering culms that generate a pluricaespitose growth habit are also called amphipodial, or (incorrectly) amphimorph,

in some systems. Species of the genera

Pleioblastus, Pseudosasa, Indocalamus, and Shibataea are examples of bamboos with leptomorph rhizomes and a pluricaespitose habit as a result of tillering culms.

Descriptions and limitations Although broadly referring to bamboos as either clumpers or runners is often all that is needed to meet the communication needs of the average gardener, grower, or landscaper, descriptions of greater precision are sometimes warranted. In these

instances, both the rhizome form and clump habit would be described separately. For example, Phyllostachys bambusoides would be described as having leptomorph rhizomes and a diffuse habit; Melocanna baccifera as having pachymorph rhizomes anda

diffuse habit; Bambusa multiplex as having pachymorph

rhizomes and a cae-

spitose habit; and so on. We have come a long way in accurately and unambiguously describing bamboo’s branching, rhizome morphology, and culm and clump spacing. Still, our terminology and concepts are far from complete, and we are still some distance from ridding ourselves of ambiguities. How far apart do culms need to be before they should be termed diffuse rather

69

70

Chapter

2

than caespitose? A rhizome

neck

length of 20 in. (50 cm)

is one

rule of thumb

(Stapleton 1994a). Growing conditions and the size and maturity of the bamboo help determine the rhizome neck length, and thus the distance between culms. How should these factors be considered in the association of a culm and clump habit with a species? Perhaps using the maximum growing conditions would

length under optimal endemic

best satisfy the needs of the taxonomist—though

not

the needs of the typical gardener, grower, or landscaper. As discussed earlier, the species Olmeca reflexa is a pachymorph bamboo with what one would readily concede is a diffuse clump habit. Its culms may be spaced as far as 26 ft. (8 m) apart. In the common

vernacular, this is certainly a running

bamboo. In my small suburban landscape, I grow Fargesia nitida and Chusquea aff. culeou. Both have pachymorph rhizome systems. The F. nitida clearly has a caespitose habit. The culms are tightly clumped and offer no threat of unexpected intrusion. But, what about my C. aff. cv/eou? Although ft.

the clump is no more than 6

(1.8 m) in diameter at the base, the culms are sometimes spaced up to 16 in. (41

cm) apart. In optimal growing conditions,

or if the clump

were

larger, the rhi-

zome neck length and culm spacing might well exceed 20 in. (50 cm). While it is

nowhere in the league of 0. reflexa, it is nevertheless sufficiently spreading that I

Like Fargesia nitida (shown

in the facing photo), Chusquea aff. culeou has a pachymorph

zome system, but the distance between culms is far greater.

rhi-

a

ce)

% 2

x oPa ad “hawe © =

£

os Bo) S@ © [oma ie) = < ee © a -

the clump a more diffuse growth habit.

Other bamboo species with pachymorph

rhizome

systems have rhizome necks that are far more elongated, with distances between culms of up to 26 ft (8 m). Clearly, pachymorph are not synonymous.

rhizome systems and a clumping (caespitose) habit

Phyllostachys viridis ‘Robert Young’ with a caespitose clump habit in cool growing conditions. In a warmer, sunnier climate, the clump habit would

be diffuse.

74

Chapter 2

need to treat it quite differently from the F. nitida. Unfortunately, I placed the C. aff. culeou in a relatively confined area near smaller plants. A new 1 in, (2.5 cm) culm penetrated a nearby dwarf rhododendron, causing a bit of a surprise. Is the clump 1am not sure—caespitose, perhaps, if one accepts the 20 in. (50 cm) rule of thumb. My gut feeling on the matter changed somewhat after the rhododendron encounter. Sometimes, distinctions are not a matter of habit caespitose or diffuse?

discrete categories, but rather shades of difference along a continuum, or perhaps manifold shades of differences along manifold continuums. Also in my garden, I have several Phyllostachys viridis ‘Robert Young’ plants that have been in the ground for nearly 10 years. ‘Robert Young’ has a leptomorph rhizome

system and a

diffuse clump

habit—at

least in the textbook context.

In

my growing conditions, the clump habit is caespitose, certainly far more so than the Chusquea aff. culeou. The culms are two stories high, but they are spaced no more than 6 in. (15 cm) apart, and typically much

cm). I would like the clumps to spread much

closer, often less than 1 in, (2.5

faster, but they have not. I live in a

fairly cool area of the Pacific Northwest. In far warmer Texas, the culm and clump habit would be greatly different, spreading aggressively with indisputably diffuse

culm spacing. In the same cool Pacific Northwest climate, many other Phyllostachys species clearly exhibit a diffuse clump habit. Culm and clump habit is a function not only of the species, per se, but also a function of the species’ response to envi-

ronmental conditions. Some species respond more dramatically to variations than others. It appears that, yet again, the terms and categories relating to rhizome

mor-

phology and clump habit are attempting to describe multiple and sometimes conflicting aspects with the same term. The words of F. A. McClure lier juncture in this conceptual

journey,

might

(1966), at an ear-

well again apply here,

when

he

states that the terms “all eventually break down in ways that leave either the original concepts or the distinctive features of associated variables somewhat blurred.”

Common vernacular is not helpful either. I would hesitate to describe Chusquea aff. culeou as a clumper without additionally qualifying the description—or as a runner, either, for that matter. Everyone knows (or at least bamboo aficionados know)

that Phyllostachys is a genus of leptomorph bamboos, and that all phyllostachys have a running habit. Neither I nor most bamboo growers or enthusiasts I know would typically refer to P. viridis ‘Robert Young’ as a clumper. Yet, in my backyard, it is—or rather, it does. As with many

things of nature, bamboo

lend itself to our attempts at convenient categorization.

does not always

GHP

TERS

Culture

Growth The yearly cycle Leptomorph bamboos have two distinct growth periods. After shooting, the culm grows to its full height. For most leptomorph species, culm growth generally ends in early to late summer, depending on growing conditions, followed by growth of the rhizomes. New rhizomes emerge from the buds of existing rhizomes, completing their growth and extension by late fall. Unlike leptomorph bamboos, pachymorph bamboos do not have a network of

underground stems, and thus do not have similar, overtly distinct growth periods. After the shooting and growth of new culms, pachymorph bamboos begin building the energy reserves needed for the following season’s shooting period, storing starches in the existing culms and rhizomes. Shooting. The shooting season is a time of great excitement, particularly in the

case of the. spring-shooting leptomorph bamboos. After what may have been a long and dreary winter, shooting bamboos

are an emphatic shout that spring is

here. Emerging from the ground at the full diameter of the new culm, the shoots thrust skyward at an astonishing rate—more than 3 ft. (1 m) in a 24-hour period for some species in an established grove. Even in a small suburban plot, a growth rate of 1 ft. (30 cm) a day is not uncommon. The branchless, rapidly elongating culms invite convenient Freudian comparisons. Such vigor is a dramatic affirmation of spring’s renewal.

TS.

76

Chapter

3

In an immature

grove, and especially in a planting only a few seasons old,

shooting shows how much the bamboo has grown. How big are the new culms relative to last year’s? How far has the bamboo spread? How many new shoots are there? Are there enough to harvest a few for the table? Unlike other plants, leptomorph

bamboos do not indicate how much

they have grown

by incrementally

increasing throughout the year or a growing season, but demonstrate their growth

and increase all at once, in a several-week shooting period in the spring. Reading about the shooting season may bring interest and curiosity, but it does not bring understanding. Only after planting bamboo one summer, waiting through winter, then experiencing the shooting season, can the enthusiasm of bamboo aficionados be appreciated. A rapidly growing timber bamboo

such as

Phyllostachys vivax helps heighten the drama. In preparation nodes

for shooting, the buds on the

of the rhizomes

begin

swelling.

As the

shoot breaks ground, its tapered tip does not fully disclose the diameter of the new culm until the shoot is several inches (8 cm or so) above ground —or

a foot

(30 cm)

or more

above ground

in the

case of a huge shoot from a mature timber bamboo. The first culms to shoot are usually the largest and most vigorous. Growth is slow at first, the rate increasing toward mid-culm, and then slow-

ing again. The time of rapid growth is called the “grand period of growth.” Warm

weather and moisture encourage shoot-

ing in leptomorph bamboos. Unusually high soil temperatures

during

the shooting

period

may

cause damage rather than forcing new growth. In one

study,

a soil

temperature

of

77°F

(25°C)

caused the shoots to decay and rot. In an area of Japan where the maximum

production of Phyllo-

stachys heterocycla {. pubescens shoots occurs during the month of April, the average soil temperature for the month

A new Phyllostachys vivax shoot.

is about 60°F

(16°C).

If late winter or early spring are unseasonably warm, shooting may begin early. If the shooting is significantly outside the normal shooting time or

Culture

if the weather turns cold, shooting may slow, or the shoots may fail to fully develop, forming compressed

internodes or aborting altogether. Rhizomes have an

abundance of buds and ¢an produce more shoots in accordance with the needs of the plant. Unseasonably cool weather may extend the shooting season. Varying periods of warmth and coolness may compress or exaggerate the differences in shooting

times among

the species. For example,

a cold early spring

will delay shooting of Phyllostachys heterocycla f. pubescens, and if the cold period is followed

by a period of very warm

temperatures,

this species may

shoot

only

slightly before P. vivax. If early spring is unusually warm, however, followed by an extended period of coolness, P. heterocycla {. pubescens may shoot early and P. vivax

will be delayed, exaggerating the difference in relative shooting times. Mature, stable groves shoot with more regularity within a more tightly defined interval than new or stressed groves. Some species, such as Phyllostachys aurea, have a tendency to continue shooting until fall, particularly if spring and summer have been cool. Late-season shoots rarely have the vigor of shoots initiated in the spring, and frost and winter cold may claim them before they are able to harden off. Occasionally, an unseasonably early shoot may emerge. Unless other shoots soon follow, the shoot is probably aberrant and not a good measure of the start of the bamboo’s shooting season. Early shoots often fail to develop properly in the out-of-season coolness.

A bamboo’s shooting season truly begins when multiple

shoots emerge simultaneously or within a few days of each other. Depending on the bamboo

and

the season, additional

Like temperate-climate

chymorph

new

leptomorph

bamboos shoot during warm,

shoots may later follow.

bamboos,

tropical and semitropical pa-

moist conditions. In their native envi-

ronments, the shooting period for these pachymorph

bamboos is not so much as-

sociated with the seasons of the year, but with environmental conditions, such as moderating

temperatures and the onset of a rainy period.

In the regions of the

United States where these bamboos can be grown, the environmental conditions

conducive to shooting typically occur in midsummer to early fall, but the times vary. In southern

California, shooting can begin as early as April, although

June is more common,

late

continuing through October until the cooler November

nights bring an end to shooting. The late-shooting culms remain branchless until the spring. Tropical and semitropical bamboos that have been severely damaged by winter cold may attempt to regenerate new culms with the onset of spring. Tropical bamboos grown indoors or in other artificial environments may exhibit all manner of shooting characteristics, as the plants try to adjust to myriad fluctua-

ai

x

Chapter 3 tions in heat from summer

sun or winter heat registers, combinations of natural

and artificial light, watering patterns, and so on. In general, the shooting period for

tropical and semitropical pachymorph

bamboos is less tightly defined than the

shooting period for leptomorph bamboos. Not all pachymorph bamboos shoot in the fall, nor do all leptomorph bamboos shoot in the spring. Species of Fargesia, temperate-climate pachymorph for example, shoot in the spring through genus Chimonobambusa vival needs.

If bamboos

shoot that

midsummer.

bamboos,

Species of the leptomorph

in the fall. Cycles are altered if mandated normally

shoot

in the fall are damaged

by sur-

by winter

cold, they will send up replacement shoots in the spring. Shooting

times vary among

species within a genus. Two timber bamboos

similar appearance, Phyllostachys vivax and P. bambusoides, shoot

weeks apart.

of

Phyllo-

stachys vivax shoots moderately early, P. bambusoides very late. Although a bamboo’s shooting period is usually intense and brief, planting a variety of species with different shoot-initiation

periods can

extend

the

shooting season.

When

planting

bamboo

for

the

edible

shoots, selecting species with different shootinitiation periods can extend the harvest season for choice

fresh shoots. Many such combi-

nations are possible. One example

might in-

clude Phyllostachys heterocycla {. pubescens, P. nuda, P. vivax, P. glauca, Semiarundinaria fastuosa, P. rubromarginata, and

P. viridis.

The short internodes of a leptomorph

rhi-

zome provide an abundance of buds for new culms and rhizome branches. Many remain in reserve,

only

becoming

active

when

ranted by the needs of the plant. Toward

warthe

end of the shooting season, some of the new shoots may stop growing and wither. This is normal, self-regulating behavior. The bamboo has expended

its allocated

reserves

for new

culms, and the shoots that have survived and A new Dendrocalamus giganteus shoot

are continuing toward maturity meet the current capacities and needs of the plant.

Culture

Culm development. In the fall, leptomorph bamboos store carbohydrates in their rhizomes in preparation

for the next season’s growth. The size potential of

the new culms is largely determined before they emerge from the soil, by the stored nutrients in the network of rhizomes. Unfavorable conditions such as cool weather,

nutrient

ment of maximum

deficiencies, and

insufficient moisture

work

against achieve-

potential. In general, the first shoots that emerge will produce

the largest, most robust culms. The last shoots that emerge will tend to be smaller and weaker. Culm growth is slow at first, with the maximum growth rate coming when the culm has reached approximately half its final height, and then slows progressively

as the culm nears the end of its growth. Growth rate is also temperature sensitive. Cool days bring noticeably slower growth. Warm days with ample moisture accelerate growth. Culm growth also can correspond to time of day. Two-thirds of the growth of a Phyllostachys culm occurs during the day, whereas some tropical bamboos grow more at night and less during daylight hours.

The major growth period of a leptomorph bamboo culm ranges from 30 to 80 days. A Phyllostachys bamboo in a favorable growing climate can reach 90 percent of its final height in 30 days or less. Tropical or subtropical pachymorph bamboos

typically require 80 to 110 days, though the final 10 percent of growth may take up to a year. The intervals of rapid growth vary among

species. The shooting period

Guadua angustifolia, for example,

and duration of the shooting period for the tropical pachymorph

begins with a three-month

bamboo

period of relatively

slow growth, followed by three to six months of rapid development. Before a new shoot emerges from the ground, the nodal diaphragms are already formed, awaiting elongation of the internodes as the culm sequentially telescopes each section. Anyone who has purchased large Phyllostachys heterocycla . pubescens shoots for the table will have seen a good example of the nodal diaphragms (also shown in the photos of the Phyllostachys vivax shoot in chapter 6). Each compressed chamber is a future internode. The extending culm is protected by the culm leaves. As discussed in the previous chapter, prematurely removing a culm leaf stops the growth of the internode. This technique is used in bonsai, when culm leaves are purposely removed early as part of the dwarfing process.

Branching and leafing. For most bamboos, branching is delayed until the new culm reaches most or all of its full height—or the branching may not take place until the following growing season, as in some species of Fargesia. The separate

ie

80

Chapter

3

branching period enables the new culms to extend rapidly without additional demands on energy reserves, and to begin hardening before bearing the burden of branches and foliage. In some genera, however, such as Phyllostachys, branching begins even as the upper internodes of the new culm continue to extend. In Phyllostachys, branch buds are immediately active, with the newly forming

branches nestling in the groove (the sulcus) along each internode. Phyllostachys branches emerge from the lower culm

nodes first and then progressively up the

culm as each succeeding internode completes its growth. In other genera, branching may begin at the top of the culm, progressing downward, or at mid-culm, progressing upward and downward. For most bamboos, branches either emerge after the culm leaf has dropped, or they push the culm leaf away from the culm, even as it remains attached at its base. In some bamboos, such as many species of Chus-

quea, the branches burst through the culm leaf’s sheath while it is still tightly attached to the culm, in a pattern known

as extravaginal branching.

Immature bamboo has branches on nearly all the nodes. The branch buds at the lower nodes of mature bamboo

may

remain dor-

mant indefinitely. In industry and craft, Pseudosasa amabilis, or Tonkin

cane, is prized for

its strong, straight culms without prominent nodes. Mature culms of the species may be branch free for as much as three-quarters of their length, thus eliminating “knots” at each node.

the branch

Leaf fall is associated with the emergence of secondary branching. In a typical spring scenario, the leaves nearest the branch axis gradually yellow and drop, new branchlets emerge,

and

new

leaves

appear

on

the

branchlets. In the spring, a mixture of green leaves and yellowing and dropping leaves is

normal and not a cause for concern. In subsequent seasons, the branches increasingly \

ae

The branches of this Phyllostachys aureosulcata f. spectabilis are developing rapidly. The culm leaf

has previously dropped away.

ramify and the leaf canopy becomes denser.

Rhizome morph

growth. The growth of lepto-

bamboo

rhizomes

begins soon

after

Culture

the new culms of spring and summer begin to photosynthesize. Growth is slow at first. The time of most

rapid growth varies according to the yearly climate and re-

gional growing conditions, but typically, growth accelerates rapidly after a leisurely growth period in June and

July. Approximately half of the rhizome growth occurs

in the months of August and September, and a third of the growth in October, before tapering to a stop in November.

Rhizome growth can be dramatic. In a fertile,

mature forest of Phyllostachys heterocycla f. pubescens, rhizomes up to 2 in diameter readily grow

12 ft.

(4 m) or more ina

in. (6 cm)

single year.

Through the end of September, photosynthesis primarily supports the growth

of the new culms and rhizomes and the grove’s heightened With the cooler, shorter

rate of respiration.

days of fall, rhizome growth slows and respiration di-

minishes. The carbohydrates produced by photosynthesis are stored as insoluble starches in the rhizomes, awaiting the following spring when

the starches are con-

verted to sugars, and another cycle of shooting and dramatic culm growth begins anew.

The branches of this Chusquea are bursting through the sheath, a pattern known as extravaginal branching.

82

Chapter

3

Growth of a clump or grove As the yearly cycles repeat over multiple seasons, clumping bamboos expand their

radius and develop into mature clumps. Running bamboos develop into a grove— or, in the case of timber bamboos with sufficient space, a forest. An individual culm attains its maximum diameter and maximum height in a single spurt of growth. In subsequent years, the culm may gain more branches and leaves, but it will neither

grow taller nor increase in diameter. As a bamboo clump or grove matures, however, it generates new culms of increasing diameter and height every year. In a healthy, developing clump or grove, the newest culms are always the largest. The maximum size of the culms is determined by the species and growing environment. Given excellent growing conditions, a small bamboo may be capable of attaining its maximum

size in a limited area typical of

a suburban plot.

A me-

dium-sized bamboo may be capable of attaining maximum size only in larger areas with excellent growing conditions. Giant timber bamboos with a running habit re-

quire a large area and ideal growing conditions to achieve their potential, typically attaining maximum

size only in native or long-established forests. Although tim-

ber bamboos may reach maximum size only in large, old forests, they are nevertheless capable of attaining impressive size and presence even when confined to a relatively small area typical of a residential property. Giant

clumping timber bam-

boos may be too large for many residential landscapes, but given the appropriate

climate and growing conditions, they can achieve their maximum

size in a rela-

tively small area, perhaps not much larger than the space occupied by a large deciduous tree with a spreading leaf canopy. The larger the bamboo, the longer it takes to approximate its maximum size. Ten years is a general rule of thumb for a grove of a large leptomorph

running

bamboo to reach maturity, although achieving a total forest environment and the

maximum size of the largest bamboos would take longer. In a study based on carbon cycling in stands of the large leptomorph timber bamboo Phyllostachys bambusoides, the projected recovery period after a 99 percent decimation of culms, simulating a period of mass flowering, was 20 years. This matches the recovery period observed in Japan. Under ideal conditions, medium-sized pachymorph can achieve maximum

bamboos

height within four years, larger species within seven years.

For all bamboos, growth gains are most dramatic in early and middle years, slowing as the bamboo approaches the maximum

that the species and growing condi-

tions allow. The shape and spread of a developing clump or grove depends on rhizome

type and growth habit. The section “Rhizome System and Clump Habit” in the pre-

Culture

vious chapter details the factors behind growth habit differences. The temperateclimate, shrubby Himalayan bamboos, such as Drepanostachyum and Himalayacalamus, have a caespitose growth habit. A developing clump of these bamboos increases gradually and more or less symmetrically.

In America,

and semitropical species of Bambusa are the most

familiar arborescent clumping

the many

tropical

rhizomes and many typically exhibit a caespi-

bamboos. They have pachymorph

tose growth habit, forming a generally symmetrical, tightly spaced clump. Other arborescent tropical bamboos, such as Guadua and Melocanna, also have pachymorph rhizome systems, but a diffuse and spreading growth habit, forming open and less

symmetrical clumps or groves. Because these are uncommon only grown

in the very warmest

in America, and

locales, tropical and semitropical bamboos

are

commonly regarded as “clumpers.” Although technically incorrect, this conception generally matches what

one encounters.

Some

bamboos,

such as Yushania,

have a pluricaespitose habit. A grove of this type of bamboo spreads somewhat irregularly, forming diffuse clumps over a broad area. A developing grove of running leptomorph bamboo, prototypically the genus Phyllostachys, evolves in a more dramatic and less predictable fashion. In the first

year or two, a newly planted bamboo will display a generally clumping, caespitose habit. Unseen above ground, the underground rhizomes will have spent the years extending a considerable distance from their origin. Initially growing in the direction their tips were pointed, the rhizomes adjust their path in the direction of favorable moisture and soil conditions, modifying direction to avoid obstacles. The rhizomes branch

into other rhizomes,

which

in turn branch again. In a mature

grove, culms are more or less uniformly distributed, but in a developing grove, new culms are quite diffuse and may appear in asymmetrical patterns at consid-

erable distances from the mother plant. A saying that may

be attributed to other plants, but seems

particularly de-

scriptive of leptomorph bamboos, goes like this: “The first year it sleeps. The second year it creeps. The third year it leaps.” The saying fairly accurately portrays the

behavior of newly planted leptomorph bamboos, initially manifesting a clumping A young leptomorph bamboo plant often develops mixed axes, sending forth rhizomes that grow underground for some distance, then turn upward to become culms. These culms are sometimes called habit before aggressively spreading.

whips or whipshoots. In their first years of growth, bamboo plants often generate

whips in addition to, or sometimes instead of, culms from buds. Whips are less erect than culms generated from rhizome or basal culm buds, and they are more prone to tip from side to side. Although less stately than a “normal” culm gener-

83

84

Chapter

3

ated from a rhizome bud, a whip’s foliage generates food and energy for the rapidly developing plant and spreads its aboveground presence. Whipshoots may appear earlier in the season than shoots from the same plant that are generated from rhizome buds. If desired, the newly emerging whips can be turned back to the soil to resume their growth as rhizomes. A small trench can be dug underneath the rhizome whip. The whip shoot is then placed in the trench and covered with soil. Sometimes it is also necessary to weight the whip to prevent it from emerging again from the soil. Leptomorph rhizomes cease growing in the fall. Typically, at least with the genus Phyllostachys, the growing tip of the rhizome dies, then the following summer, new rhizomes branch from buds near the end of the living part of the rhizome. Rhizomes rather than culms tend to develop from the buds near the tip of the rhizome. In a young system, rhizome branching is often numerous. In older systems, rhizomes may continue for several seasons without the tip of the rhizome dying. When

the tip of a rhizome does die in an older system, only one or

two rhizome branches may develop, or a single rhizome branch may simply carry

on in the general direction of the original tip. In the first years of a maturing system, leptomorph rhizomes retain the capacity to turn upward and become culms. Rhizomes in a mature system no longer have this capacity, and a rhizome will die if it does turn upward. In a mature system, a rhizome tip can continue living and extending for several years. As long as the tip continues growing, no branching occurs.

Bamboos with pachymorph rhizomes and a tight clumping habit tend to have the newest

culms

on the perimeter,

and

the oldest culms

in the center of the

clump. To the extent that new rhizomes and culms spread inwardly, they tend to grow on top of the existing mass of rhizomes and roots, forming a raised mound.

The center of an old clump will tend to have culms that are fewer and older, sometimes making way for the growth of other vegetation. Although a culm attains its maximum

height and diameter in its first year of

growth, its branches may continue to ramily. Bamboos may have a spring period of leaf fall, as the lower leaves on a branch drop away, replacing the leaf with a new branch

with leaves or branches at each

of its nodes.

Each succeeding

year

can bring increasing ramification, creating a profusion of branches and leaves. Alternate-year cycles. Some Chinese bamboo forests are classified as either odd-year or even-year

forests. Most

natural

forests are odd-year forests. Newly

Culture

matured culms shed and replace their leaves at about the end of their first year, and every other year thereafter. In an odd-year forest, most culms replace their leaves in the same year. Thus, in a given year, the culms in an odd-year forest will replace

most of its leaves,

followed by a year when

their leaves. Shoot production

most culms do not replace

and leaf replacement

are related. Many

more

shoots are produced during years when the leaves are not replaced. In an odd-year forest, shoot production varies widely from year to year. For commercial shoot production,

an even-year

forest is generally desirable.

In an even-year

forest,

roughly half the culms replace their leaves each year, thus shoot production is relatively uniform from year to year.

A new grove may exhibit either an even- or odd-year shooting and leafing pattern depending on the cycle of the plants used in establishing the grove. In the

suburban landscape, a “grove” is often established from a single plant, and thus may exhibit a distinctive odd-year cycle, producing many shoots one year and relatively few the next. The cycles are subject to considerable modification, however,

depending on yearly variations in water, nutrients, and other climatic conditions. In a developing grove, the size and productive capacity typically increases significantly from one year to the next, thereby muting the effects of odd-year cycles. Diseases, pests, unusual weather, insect defoliation, and poor management practices that cause stressed conditions can transform an even-year forest into an odd-year forest. The tendency to harvest a higher percentage of the sparsely available shoots in an off year of an odd-year grove only serves to exaggerate the oddyear effect. By the same token, an odd-year forest can be transformed into an even-year forest by retaining a higher percentage of shoots and new culms during the off year. Dynamic equilibrium. Once established, commercial groves are maintained in a state of vigorous equilibrium. Old culms are thinned to make way for new culms on a replacement basis. The most robust new culms are selected for the replacement

culms.

A typical shoot-producing

Phyllostachys heterocycla {. pubescens

forest, for example, is thinned to a density of approximately 800 culms per acre (2000 culms per hectare). The culms may be topped so that sun can better reach the soil and promote earlier shoot emergence and shoot harvesting. Old culms are harvested when they are about seven years old, at a rate of about 115 culms

per acre (285 culms per hectare). Each year, approximately the same number of

new culms is allowed to grow to replace the harvested culms. The new culms are marked with the year of their emergence so that they can be cut at the appropri-

85

86

Chapter

3

ate age. A grove intended primarily for culm production can be maintained with a greater density of culms per acre, promoting straight culms that support

them-

selves in strong winds with little or no topping. The replacement cycle will typically be shorter, since culms attain maximum strength in about three to five years. A bamboo grove maintains a dynamic equilibrium by generating new shoots and killing excess culms. If the grove is unable to sustain the culm biomass, excess culms are killed until food consumption

no longer exceeds food production. The

grove may kill shoots if it can no longer sustain their growth.

This often occurs to-

ward the end of the shooting period, when the last shoots that emerge from the ground are aborted. The grove may also generate new shoots outside of the normal shooting season, if new culms are necessary to maintain the grove. Chimonobambusa, for example, normally shoots in late

summer growth

or

fall,

but

if the

aboveground

experiences severe damage,

winter kill, the plant

will generate

such as replace-

ment culms in the spring. A general flowering of a bamboo clump or grove

is an

infrequent,

major

event—one

that can mark its death. Refer to the “Flowers and

Flowering”

section

in chapter

2 for a

more detailed discussion of flowering.

Forest ecology Forest ecology is an extraordinarily complex

and vital topic, made all the more so as human populations

and

technology

major and sometimes defining

evolution, and

sometimes

have

become

factors in their

in their demise.

The treatment of the topic in this book is very modest, merely offering a flavor of the complex interactions among forest species. Many period

bamboos

are

of gregarious

monocarpic. flowering,

After a

recovery

is

mostly or exclusively by seedlings. Bamboos Excess shoots are aborted to maintain the grove’s equilibrium. In this Bambusa clump, the old,

aborted shoots are a ghostly white.

frequently

dominate the understory or over-

story in forests. The sudden demise, brought about by gregarious flowering, of what had

Culture

been a dominant plant in the forest understory or overstory creates a dramatic shift in the forest ecology. The flowering cycle of Sasa has been variously placed between 60 to 100 years or more. Dominant in many grasslands and forest understories, the flowering and demise of the monocarpic Sasa afford the opportunity for the invasion and establishment of many new species. The Sasa seedlings compete with other invading vegetation and require

15 to 25 years before the plants attain full size and regain

dominance (Makita 1992). An understory plant, Sasa is a determining factor in the growth cycles of the forest overstory and understory. Sasa flowering cycles are important

dynamics

in Japanese beech

forests. A

Sasa understory inhibits the establishment of beech seedlings. The lengthy vege-

tative state of Sasa, followed by flowering, death, and a lengthy recovery cycle, allow beech seedlings to establish and grow above the competition in the understory. The mass flowering of S. kurilensis in 1995, covering some 2500 acres (1000

hectares) in the beech forests in northern Japan, is providing researchers across a broad range of disciplines the opportunity to study the effects on the ecologies of these forests. Similar cycles are observed in New World beech forests as well, though instead of Sasa, these cycles are played out with Chusquea. Certainly not exclusive to beech forests, similar cycles are repeated in evergreen forests in the Himalayas and elsewhere. Flowering cycles affect the forest understory as well. In the Hira Mountains of

central Japan, Sasa tsuboiana flowered gregariously in 1977. In one area of the mountains, Miscanthus sinensis, an herbaceous grass, became dominant in the un-

derstory after the gregarious flowering of S. tsuboiana, suppressing the regeneration and vigor of the bamboo.

After about

10 years, S. tsuboiana regained dominance,

and the shade-intolerant M. sinensis declined rapidly. In other regions of the moun-

tains, 13 years after the gregarious flowering of S. tswboiana, other shrub species remained more widely distributed than they had been before the gregarious flowering—and

remained

so even after the general recovery of S. tsuboiana. In this

instance, the predominance of S. tsuboiana is likely to continue a gradual increase over the years. Human

intervention can also cause precipitous changes in forest ecologies. In

a typical scenario, repeated with many different species in many parts of the world, burning, logging, and land clearing eliminate the overstory, enabling colonizing plants that thrive in the sun to rapidly dominate. Typically, where it is native, bamboo wins the contest. In these situations, bamboo

may form vast, dense thickets,

excluding other vegetation and earning an unfortunate reputation as a weed.

87

88

Chapter

3

On a more pleasing note, a dominant forest of timber bamboo substantially creates its own environment, in which it then thrives. For example, in a Phyllostachys heterocycla {. pubescens forest, the towering culms and masses of foliage form a dense canopy that shades the forest floor and shelters it from drying winds and extremes of heat and cold. The forest floor is covered by dense mulch built up from decades, or perhaps centuries, of leaf fall. The mulch prevents the soil from drying, moderates temperature extremes, and inhibits the growth of other vegetation. The mulch provides an ideal medium for many mushrooms. In China, harvesting a bamboo forest may include gathering edible mushrooms as well as bamboo shoots.

Growth habits under adverse conditions Like most plants, when

faced with adverse circumstances, bamboo

adjusts its

growth habits to best ensure its chances of health and survival. If bamboo is unable to supply its leaves with adequate moisture, the plant attempts to preserve moisture by reducing the leaf surface area exposed to the air and sun. Bamboo

under

moisture stress begins to curl its leaves. A severely stressed plant will tightly roll its leaves into the shape of needles, reducing the leaf surface area to an absolute min-

imum. This phenomenon

is made possible by the collapse of large cells near the

leaf’s surface, called bulliform cells, that cause the curling and rolling effect. If this mechanism

proves inadequate, some leaves will turn brown, die, and drop from

the plant. Some bamboos, such as species of Yushania, curl their leaves in direct sunlight, but this is an adaptation and not necessarily indicative of a problematic condition. When

confronted with abnormally low light, bamboo will drop leaves until

the plant is in balance with prevailing light levels. It is common

for a bamboo

drop many leaves when brought indoors from an outdoor environment. door conditions are not extreme,

to

If the in-

the plant will gradually adjust to the reduced

light. Although bamboo grown in less than optimal light will not be as vigorous as

bamboo grown under optimal conditions, the ability of bamboo to adjust permits a healthy and attractive plant to be grown in a wider range of environments.

Depending on the species, a leptomorph bamboo and spread less in situations of low light.

will grow less vigorously

A shaded environment will not deter the

running habit of a Sasa bamboo that prefers shade, but the same conditions will engender a clumping habit from a Phyllostachys bamboo that otherwise would have displayed a strong running habit in sunny, optimal conditions. The Phyllostachys bamboo in shaded conditions would also exhibit a general reduction in vigor and much

smaller culms.

Culture

Growth is also inhibited by conditions that are either too warm or too cool. Many

temperate-climate bamboos

need a period of cool weather dormancy,

or

else the subsequent year’s growth will be weak and the plant will continue to lose vigor. Winter cold damage can progressively affect the plant. First the leaves brown and wither, then drop, followed by death of small branches, then death of the larger branches, death of the culm top, then death of the entire culm. Under severe conditions, bamboo can be killed to the ground, then grow back again the following spring. If the rhizome system is killed, however, the plant dies. Every bamboo

has a normal shooting season, but under adverse conditions,

shooting may occur at any time during the year. Temperate-climate

bamboos

grown in subtropical conditions or subtropical bamboos grown in temperate conditions may shoot outside their normal season. When grown in America, many subtropical bamboos initiate shoots in late summer or fall, but if cooling weather inhibits shooting, or if the tender shoots are killed by winter’s cold, new shoots may be initiated the following spring, as the bamboo adapts to ensure its vigor and survival. For leptomorph bamboos, culm and rhizome growth normally occur sequentially during the course of a season. A stressed bamboo may forego culm growth during a season, generating rhizome growth only.

A new rhizome ensures that

there will be viable buds to generate both new culms and new rhizomes. Without

viable buds, the plant cannot generate either new culms or new rhizomes, and it will gradually weaken and die. Although most bamboos normally flower at lengthy intervals, with the entire

plant bursting into flower, a plant may generate a few flowers on isolated branches if growing under stressed conditions. This is presumably a protective reaction to produce flowers and seed in the event that the mother plant dies.

Cultural Requirements Natural bamboo distributions range from tropical to temperate zones, from sea level to more than

14,100 ft. (4300 m) in the equatorial

highlands of South Amer-

ica, and from approximately 47°S latitude in southern Argentina to 50°N latitude on Russia’s Sakhalin Island. In spite of this broad distribution to widely varying growing regions, the cultural requirements of bamboo are remarkably similar among the manifold genera and species. Bamboos differ most in their preference and tolerance of heat and light.

Bamboo achieves its full growth potential only under ideal conditions, yet this enduring grass can adapt and survive in environments that are far less than ideal,

89

90

Chapter 3

and thrive in good, if not ideal conditions. For the gardener, grower, and landscaper, this means that a relatively wide range of species can be successfully grown in a relatively wide range of environments. On the other hand, if achieving max-

imum growth potential is the essential goal, only a few bamboo species will be ideally suited to any given environment. In general, bamboos are highly adaptable and easy to grow. Bamboos are also highly responsive plants that generously reward the grower who favorably augments their growing conditions.

Soil Although bamboo is a tenacious survivor under adverse conditions and is not particularly fussy, the best soils promote rapid growth and the most attractive and productive groves. Bamboo prefers fertile soils rich in organic nutrients. Ideal soils for most bamboos are slightly acidic, loosely textured, and well aerated. They should drain freely, yet retain moisture. Water-saturated, soggy, heavy soils exclude air from the root system, keep soil temperature low, and can cause rhizomes to rot. Tolerance of less-than-ideal most

bamboos,

soil conditions varies among

Phyllostachys prefers loose, well-drained

bamboos.

Like

soils that are rich in or-

ganic matter, but many in the genus are also tolerant of heavy clay soils. By contrast, species of Fargesia are generally exceptionally sensitive to soil drainage and may not survive in heavy clay soils. An example of an excellent bamboo soil is a slightly acidic, sandy loam with a pH of 5.5 to 6.5. Highly alkaline soil impedes the availability of water to the bam-

boo, a particularly critical concern during the intense period of shooting and culm growth. Growing regions where alkaline soils are prevalent are also typically hotter, drier areas where adequate water is already a concern. Soils in these areas are typically deficient in organic material and may be deficient in sulfur that would otherwise be generated from organic material. Chlorosis may be a result from sulfur deficiencies, lack of iron, or other causes. Some bamboos tend to prefer more acidic soil. Shibataea kumasaca is exceptionally sensitive to leaf burn from alkaline soils and does best in quite acidic soils.

Somewhat unusually, a few bamboos, such as Otatea acuminata ssp. aztecorum, reportedly prefer a slightly alkaline soil. Certain bamboos are more tolerant of a range of soils. Semiarundinaria

fastuosa

is typically grown in moderately acidic soil

but is reportedly very tolerant of alkaline soils with a pH of 8.0 or above. Even within the same genus, tolerance for soil acidity varies. Phyllostachys nigra

and P. nigra var. henonis are reportedly more tolerant of acidic soils than P. heterocycla f. pubescens. If the soil is too acidic, P. heterocycla {. pubescens foliage will readily

Culture

become chlorotic. Curiously, P. heterocycla f. pubescens is more particular about growing conditions than others of the genus, and it is also intolerant of alkaline soils. Sandy soils benefit from additions of organic materials. Clay soils can be im-

proved with additions of sand as well as organic materials. A wide range of materials are suitable for organic additions, availability often being among the principal

reasons

for choosing

one

over

another.

Some

examples

include

chipper

material, composted nonwoody plant refuse, sawdust, fir bark, hay, apple or grape pomace,

composted

manure,

leaf humus,

bark chips, peat, and so on. The woody

materials deplete nitrogen as they decompose and so necessitate nitrogen augmentation, a matter easily addressed during normal fertilizer applications. Com-

posted manures make an excellent soil amendment

when preparing an area for

planting, contributing texture along with fertilizer and organic nutrients. Manures

that have been reduced to a fine powder hinder rather than help soil aeration and permeability. The best manures for soil augmentation have some texture. Although the soil should be well cultivated and loose, it does not need to be

cultivated very deeply. Even in Japan’s giant Phyllostachys heterocycla f. pubescens forests, soil was traditionally cultivated only to a depth of 2 ft. (0.6 m) in clay soils, and only to about

11% ft. (0.4 m) in sandy loam soils or soils rich in humus. Al-

though rhizome depth reaches 3 to 4 ft. (1 to 1.2 m) in the giant forests, viable rhizomes typically grow much closer to the surface, and ideal rhizome depth is generally considered to be no more than 1'” ft. (0.5 m).

Mulch Bamboo

benefits greatly from a top mulch. A layer of mulch

and root system warm

keeps the rhizome

and moist, protects it from excess heat or cold, and cycles

nutrients back to the soil. In areas with very severe winters, a winter layer of mulch 1

ft. (30 cm)

or more deep may

be essential for health and survival. For

most situations, a layer of mulch one to several inches (2 to 10 cm) deep will suffice. Ina controlled test on the effectiveness of mulch, the greatest soil temperature

increases occurred in December and January, often the most critical months for cold protection. Mulching promoted the early emergence of new shoots and prolonged the shooting period. In the study, the shooting period, and thus the harvest

period for shoots, was increased from one and a half to as much as three months (Cao et al. 1996).

A mature grove provides its own mulch from leaf fall, but a new planting will benefit from augmentation. Leaves, leaf humus, and composted manure work

91

92

Chapter

3

particularly well. Straw, hay, lawn clippings, pine needles, wood chips, and bark, among others, are additional possibilities that can be used alone or in conjunction with other materials. In general, regardless of the climate or the particular requirements of a given

species, a good top mulch is highly desirable. the environment

and

protects

the bamboo

A top mulch tempers the effects of

from

of heat,

extremes

cold,

and

drought.

Fertilizer Ideas regarding fertilizer regimens have varied over the years. A 19th-century book called The Cultivation of Bamboos in Japan

(Satow

1899)

recommends

the fol-

lowing:

The dead bodies of dogs, sheep, cats, rats and other animals, the skins, bones and hoofs of cattle and horses, are the best for this purpose. Decayed rice and wheat plants, rice and barley bran, and other vegetable matter, ashes, the contents of the dust-bin, rotten compost, stable litter, the dung and urine of men and horses, and lime where the soil is not sandy, may all be used.

Confronted by the lack of a ready supply of horse hoofs and dead sheep, the modern suburban gardener is forced to turn to other fertilizer sources. In general, a fertilizer mix suited to growing grass in a given area should also do well with bamboo. A full-range fertilizer of phosphorus, potassium, and a relatively higher amount of nitrogen is generally suitable. Bamboo also responds very favorably to organic manures. One method calls for a generous top dressing of organic manure one year, followed by non-organic fertilizers the following year. Had I the resources,

conditions,

fertilizers. As it is,

and time to permit

it,

| would

probably

use only organic

| use a combination of the two. There are probably as many

favorite fertilizer regimens as there are bamboo growers. The most important time to apply fertilizer is when the new shoots are form-

ing underground. Depending on the local climate, February, March, or April are the prime times to begin the new year’s fertilizing regimen

for most leptomorph

bamboos. For pachymorph bamboos, the time of the year will depend on the species and the growing conditions, but the same principles apply. Except for the winter months, bamboo is actively growing most of the year, producing and extend-

ing new culms, branches, and leaves, or producing and extending rhizomes. The best regimen calls for fertilizing just prior to shooting, and then continuing peri-

Culture

odically throughout the active growth period. More frequent fertilizing is appropriate where heavy rainfall leaches the nutrients from the soil. Where winter freezing is a danger, caution must be exercised not to overfertilize in the fall and winter. While it may be tempting to incorporate organic fertilizers in with winter's protective mulch,

this could subject the bamboo

to severe

winter damage. Slower acting, organic fertilizers can be applied in late winter or early spring after the danger of hard freezing has passed.

Bamboos,

particularly

the vigorous

plants. Like lawn grass, bamboo

timber varieties,

are nitrogen-loving

responds to generous fertilizer applications. Some

degree of caution and common sense must be exercised, however. A large, vigorous, timber bamboo

may

not immediately

show

the typical effects of excessive

fertilization. As an experiment, I once applied massive quantities of nitrogen to a small grove of Phyllostachys vivax. New culms shot prolifically, grew vigorously, and

the grove appeared healthy. The weight of heavy summer rains, however, revealed the weakened state of the culms, bending and splitting them beyond recovery. The following year yielded very few new shoots and no advancement

in size. Bamboo

is a heavy feeder, but common sense must prevail. The fertilizer regimen can also be adjusted in accordance with the grove’s intended use. Heavy fertilizer applications are desirable for maximum

shoot pro-

duction. If high-quality culm wood is the principal aim, however, more moderate fertilizer applications would be in order, to ensure the strongest culms.

Water Although

most bamboos

are relatively drought

resistant, they only thrive with

ample water. The roots, however, must not become waterlogged. Except for a very few species that have air channels

in their rhizomes, such as Arundinaria gigantea

ssp. tecta and Phyllostachys heteroclada, bamboo will not grow in water-saturated, swampy, or boggy conditions. Ideally, the soil should always be moist, but never soggy. For most bamboos,

overwatering is not a concern as long as the soil is well

aerated and free draining. A once-a-week watering regimen is a good starting point, but actual watering needs and frequencies will vary widely—from not at all during rainy periods, to

every day in exceptionally hot, dry conditions with poor soils and little or no

mulch. In drier climates, bamboo benefits from misting, which creates a more lo-

cally humid environment and discourages bamboo mites, aphids, and the like. Proper soil and mulching make watering easier. Many soils shed water when they are dry. Soils containing sand and organic materials help encourage water

93

94

Chapter 3 penetration which,

and

absorption

even

unless moist, tends to shed

dry. Peat

when

moss

is a notable exception,

water. A layer of mulch

helps keep the soil

moist, diffuses incoming water, and helps it penetrate the soil.

Ample soil moisture is one of the principal triggers that initiates shooting in many tropical bamboos, because it signifies the beginning of the wet season and the period of active growth. All bamboos benefit from ample water during active growth periods. For most leptomorph bamboos, this period begins just prior to shoot initiation in the spring and continues through the succeeding stages of culm growth, branching, and leafing, through midsummer, followed by rhizome growth from midsummer through fall. These bamboos are well matched to their native Asian climates, where the periods of active growth coincide with the wet season. America’s

West

Coast and

Mediterranean

European

climates,

however,

receive

most of their yearly precipitation during periods when the bamboos are dormant or not actively growing. In these regions, even when the temperatures during the growing season closely match those of the native Asian environments, the lack of

moisture during the active growing periods limits growth. In these climates, maximum growth is not achievable without irrigation, siting in riparian zones, or some other supplemental water source.

Rhizomes, and subsequently their culms, can be encouraged to grow in certain areas, and discouraged in other areas, by ensuring that the desired areas are gen-

erously fertilized and watered. Withholding water and nutrients from an area during the period of rhizome growth is one method of guiding and limiting the spread of running bamboo. It is most effective when the natural growing conditions are dry and nutrient poor. Control and encouragement

is only a matter of degree,

however, and this method of controlling growth is generally insufficient on its own.

Bamboo leaves curl when

the plant is water stressed, and so leaf curling is

usually a sign that watering is quickly needed. In severe circumstances, the leaves will roll so tightly that they begin to resemble needles. With a newly propagated

bamboo, however, leaf curling may indicate that the bamboo is carrying too much foliage for its root system. Some species naturally curl their leaves when exposed to sunlight, even when

they are not water stressed. For the most part, however,

leaf curl is a reliable indicator that the bamboo needs water. Large bamboos in containers becomes water stressed more quickly than bamboos grown

in the ground, and they should be monitored more closely during

hot, dry periods. A bamboo that is becoming root-bound in a container will need watering more frequently. If a bamboo

in a container is drying out more quickly

Culture

than other bamboos in containers, this is an indication that it needs to be divided or needs a larger container.

Heat and light With respect to their cultural requirements, bamboos differ most in their prefer-

ence and tolerance of heat and light. The chapter on the genera and species of bamboo

(chapter 9) describes the general requirements for each bamboo,

but

more factors are at play than can be readily summarized in a listing. The temperate-climate groundcover bamboos are generally understory plants that prefer some shade. This is especially true in a climate like that of southern Ca-

lifornia, but in maritime climates, such as those in parts of the Pacific Northwest, the same groundcovers may thrive in full sun. Even more than the groundcover bamboos,

many

Fargesia need shade,

yet in parts of cool, cloudy England,

they

thrive in full sun, Unlike most of the groundcover bamboos, however, most Fargesia are intolerant of heat. In hot southern climates that groundcover bamboos could readily tolerate, Fargesia may grow poorly—il at all. Unlike most Phyllostachys, P. nigra prefers less than full sun in hot, sunny climates. In the maritime Pacific Northwest,

however, P. nigra not only thrives in

full sun, but also achieves a diameter and height that, for the species, is among the largest in the world. On the other hand, these same parts of the Pacific Northwest

are much cooler than is ideal for warmth-loving species like P. makinoi. Both P. makinoi and P. vivax prefer full sun, but P. makinoi needs much more heat to achieve

its growth potential. In the maritime Pacific Northwest, P. makinoi never achieves a size that approximates its growth potential, yet it readily does so in Texas. Phyllostachys vivax is more tolerant of cooler conditions and grows rapidly and large in the

Pacific Northwest. In parts of cool, cloudy England, P. bambusoides, the large timber bamboo,

may only achieve a diameter of 4 in. (2 cm), and the warmth-loving

P. heterocycla f. pubescens, even less.

Many leptomorph bamboos will thrive in environments with the same hot, sunny summers that benefit the pachymorph semitropical and tropical bamboos But unlike the tropical genera, most leptomorph bamboos, including most species of Phyllostachys, need a period of cold and winter dormancy, or else future growth will be scraggly or severely limited—if the plant survives at all. Some of the montane bamboos, such as species of Drepanostachyum and Hima-

layacalamus, are only moderately winter hardy, sometimes little more so than the more robust semitropical species of Bambusa, yet these relatively cold sensitive montane bamboos still need a period of winter cool. Over an extended period of

95

96

Chapter

3

time, the montane bamboos seldom do well as houseplants under normal, warm,

in-home winter temperatures. By contrast, Bambusa and other semitropical and tropical bamboos are accustomed to year-round warm temperatures and can make

good houseplants if humidity and light are sufficient. The rate of photosynthesis varies with temperature, available daylight, and seasonal changes in the bamboo plant. A study of P/ryllostachys bambusoides (Koya-

ma and Uchimura

that the maximum

1995) showed

early July and November.

curred between

rate of photosynthesis oc-

The least photosynthesis occurred

in

May, coinciding with seasonal leaf fall and the rapid growth of the new culms, a period when the bamboo requires a great deal of water for the new shoots. Photosynthesis also decreased when

temperatures rose above 80°F (27°C), as the need

for rapid respiration limited photosynthetic efforts. Specific responses to seasonal and temperature changes are likely to vary somewhat from this example, particwith their different seasonal environments

ularly for tropical bamboos,

and cli-

matic adaptations.

Winter hardiness Cold hardiness varies widely among bamboos. Some

tropical species suffer dam-

age as soon as the temperature drops to 32°F (0°C). Other bamboos can withstand

cold to -20°F (-29°C) without damage. In general, most pachymorph bamboos are semitropical or tropical and are far less hardy than leptomorph bamboos, but there are exceptions.

Some

species of Fargesia,

a genus of pachymorph

bamboos,

are

among the most hardy of all bamboos. One needs to keep in mind that the mini-

mum

temperatures cited in this book and elsewhere are only approximations.

Wind, humidity, sun, duration of low temperatures, soil moisture, and so on, all play a role in determining whether or not a bamboo will be damaged. Also, some varieties and ecotypes may others of the species.

exhibit different cold hardiness characteristics than

Arundinaria

gigantea ecotypes, for example, vary significantly

in cold hardiness. By convention,

the minimum

temperatures cited in this book refer to the

point at which leaf damage begins to occur. If cold temperatures are persistent rather than brief, the damage

will be more severe and will begin at higher tem-

peratures than those cited. In general, if continuing low temperatures at or near the minimum are expected, a more cold-hardy bamboo may be preferable. Bamboos can, however,

be grown in climates with colder temperatures than

their cited minimums if one is willing to understand and accept limitations in size and seasonal appearance. Although far from ideal, bamboo can even be grown in

Culture

areas with severe winters and treated like a renewable perennial, cutting away all

the aboveground growth each year, then enjoying the fresh new culms and leaves in the spring, summer, and fall. If not all of the aboveground growth is killed in a given year, growth the following spring will tend to be more robust, and the culms larger. Winters that bring total aboveground mortality will tend to engender a regression in vigor and culm size the following spring. A few bamboos are naturally deciduous in winter. More markedly, some of the

Himalayan bamboos act as herbaceous perennials in their native environments, dying to the ground in winter’s cold, then sending up new growth in the spring. They continue to flourish, but will grow much larger and take on a different character when cultivated in an environment with milder winter conditions. Many bamboos can be grown with little or no winter protection in parts of the United States, but where winters are severe, or when one wants to grow species that normally require warmer conditions, cold protection methods are warranted. Bamboo is commonly regarded as a plant suitable only for southern and coastal zones, but with careful species selection and winter protection, bamboo can be successfully grown, with limitations, throughout the country, including the northern interior (Hawke

1992) and Alaska.

Various reports by growers confirm that bamboo can be grown even in climates with severe winters. Sasa senanensis reportedly suffered only moderate leaf damage after a New York winter with little snow cover and occasional temperature drops to -30°F

(—34°C).

In the same

report, Phyllostachys bissetii was bent to the

ground and covered with mulch, and it was able to retain its green leaves. In another report, approximately 50 species of bamboos were subjected to temperatures that dropped

to -31°F

(-35°C). The bamboos

had about

10 in. (25 cm) of

snow cover. All the species were killed to the snowline, but none were killed completely, and all generated new culms in the spring.

Because hardiness ultimately depends on so many factors, experience is likely to vary widely. One report from Tennessee cites twig damage to Fargesia nitida and F. murielae, reputedly among the hardiest bamboos, at —5°F (—21°C). A grower in Norway reports that the same bamboos experienced a temperature drop to —20°F (-29°C) with only loss of leaves (which were replaced in the spring), but no other

damage. Snow cover, or a mulch that covers the entire plant during severe cold, greatly enhances the winter hardiness of bamboo. Note, however, that if the mulch is dense and does not permit air circulation, the bamboo’s green leaves may themselves become “mulched,” necessitating the generation of replacement leaves

in the spring.

ME

98

Chapter

3

Drying winds can severely damage foliage and may cause or contribute to even more extensive damage. In one report from New England, mild fall weather was followed by sudden Arctic winds. All species that were exposed to the winds suffered total leaf kill. Specimens of the same species that were protected in a woodland environment remained green. Preventing winter desiccation is critical to bamboo’s

health and survival, particularly when

temperatures approach

the

minimum limits for a given bamboo. Rain, snow, watering, misting, plastic tenting, mulching, and anti-desiccants can all help prevent winter damage from desiccation.

In addition to harsh winds and persistent periods of cold, radical fluctuations in temperature can also contribute to further damage even if low temperatures are

not that extreme. In the Pahrump Valley of Nevada,

September temperatures can

drop below freezing one day and be immediately followed by temperatures reaching 95°F (35°C).

In January

temperatures may

climb to 70°F

(21°C)

for two

weeks, creating budding situations in deciduous plants and initiating growth in bamboo, followed by a week or more in February when temperatures drop to 10 to 15°F (-12 to -9°C). The

Pahrump

Valley climate also includes drying desert

winds and high pH clay soils. In this relatively hostile environment,

not be said to flourish, yet

bamboo can-

a number of species, such as Phyllostachys decora and

Semiarundinaria fastuosa, are reportedly viable and rewarding.

Although bamboo may only truly flourish in climates that mimic a species’s native environments, bamboo is far more adaptable than once assumed. If one is

able to accept smaller culms, or a deciduous habit, or perhaps even a perennial growth habit of winter culm death followed by regenerative growth in the spring, bamboo can be grown successfully throughout most of the world. Careful species

selection and cultivation will greatly enhance the opportunities. Types and degrees of cold damage. Cold damage has a progressive pattern of severity, ranging from leaf browning and damage, leaf drop, damage to branches and culms, culm death, partial death of the rhizome system, and complete death of the plant. Each stage of damage has a progressively negative effect on a bamboo’s vigor and growth potential. If all the rhizomes die, the plant dies. Bamboo

with minor leaf damage will look a bit tattered, but any effect on

vigor and growth potential will be negligible. Dropped leaves will be replaced with new leaves in the spring, or new branches and leaves, but the bamboo will incur a period of lost or reduced photosynthetic capability. Bare branches detract from

aesthetics and may mean a lost or reduced screen from neighbors or passersby.

Culture

Branch and culm damage, and especially culm death, seriously impact vigor,

aesthetics, and screening. It is usually best to wait until late spring before remoying leafless branches and culms. After winter defoliation, the branches and culms are sometimes able to generate new leaves from reserve buds. Damaged and dead

culms can be removed, and the rhizome system will generate new culms, but the vigor and growth

potential of the bamboo

will be severely affected. Even

if the

culms are killed to the ground each year, it is still possible to grow marginally hardy bamboos in areas with difficult winters. Although the bamboos will never approach

their maximum

size potential, many of their attributes can still be ap-

preciated. If some of the rhizomes are routinely killed, however, long-term survival will be in doubt. Preventing and reducing damage. Thick mulch is essential for severe winter areas. Above all, the rhizome system must be protected. Even if culms are killed to the ground, a healthy rhizome system will be able to generate new replacement culms in the spring. A layer of mulch 6 to 12 in. (15 to 30 cm) deep is often suffi-

cient, but if extreme conditions are expected, much deeper mulch may be warranted. If possible, protect bamboo from the wind. Spraying the leaves with an antidesiccant can help prevent moisture loss and leaf damage in areas where cold, drying winter winds

are a problem.

In some

instances,

culms

can be bent to the

ground and covered with insulating material, such as evergreen tree boughs, straw, burlap, or any combination of materials that will keep the culm weighted

down and provide insulation. Snow protects bamboo from cold and drying, but it can also break branches and culms.

Small bamboos can be protected by water-

filled, plastic, topless tents of the sort sold for protecting tomato plants in the spring. Bamboos in containers are most vulnerable to cold damage. The soil should be kept moist, and the bamboo may require watering even in the winter. Grouping containers tightly together creates a larger mass that resists freezing. Tightly clustered foliage also has an insulating effect. More vulnerable species can be placed nearer the center of the grouping. Pile mulch, bark, wood

chips, and other such

materials around the sides of the container or group of containers, or cover with

a tarp, creating a pocket of air connected to the ground or heated building. A greenhouse greatly expands the range of bamboo that can be grown in cold winter areas. Warmth and moisture help determine when bamboos shoot. Warmth is more of a factor for temperate-climate species, moisture more of a factor for tropical

99

Borinda fungosa in late winter. The leaves, branches

tained cold damage.

and upper portions of the culms have sus-

Gs

2

ee

di

te,

oa

=a

The same Borinda fungosa plant in midsummer of the same year. The winter-damaged culms were pruned back. The new growth is lush and attractive.

102

Chapter

3

and subtropical species. These shooting tendencies can be a factor in cold damage in some climates. Warming sun and a period of elevated temperatures can stimulate early shooting species. If this is followed by frost and freezing, the new shoots can be damaged or killed. In parts of the American Southeast, for example, bright sun, pronounced temperature variation between summer and winter, and erratic early spring weather put early shooting bamboos

at risk. The risk can be mini-

mized by planting on sites that are not heavily exposed

to late winter and early

spring sunlight (such as slightly north-facing slopes), by covering the new shoots with mulch

if a return

to cold temperatures

is expected,

and

by planting

later

shooting varieties. Planting bamboo so that the foliage is in sun but the ground and rhizomes are in shadow is another way to delay shooting.

In parts of the Pacific Northwest, as another example, the concern is often the opposite. Spring weather is less erratic, but cool summers

mean

that some late

shooting varieties may not shoot early enough to allow the new culms to leaf out

and harden off before the onset of winter. The rhizome growth period that follows shooting may also be delayed, thus impairing the development

of a clump or

grove. In this type of climate, later shooting varieties should be planted in warmer, sunnier growing sites. Clay soils can be amended so they warm faster. Mulch can be pulled aside so the soil warms more quickly, or various black or darkly colored warming tarps or cloths can be placed to warm

the soil.

In American growing environments, some bamboos, particularly semitropical

and tropical species, naturally shoot in late summer or early fall. If late summer and early fall are dry, shooting may be delayed and still be in progress when

the

colder temperatures of winter begin to intrude. Keeping these varieties well watered during summer and early fall will encourage them

to shoot earlier and es-

tablish their growth before the onset of colder temperatures. When choosing a site for bamboo, or a place to cluster containers of bamboo for the winter, remember that cold air flows downhill and pools in low-lying areas orin front of objects, such as buildings, that block or impede the continued flow of

cold air downhill. If winter hardiness is a concern, low-lying areas, and other areas that will pool cold air, should be avoided. Forgetting this basic rule, and not paying

attention to the lay of the land, cost me the loss of several bamboos one winter.

Environmental stresses and extremes A variety of environmental factors affect the health and vigor of bamboo. Generally, low humidity is a potentially greater concern than high humidity, exaggerating the effects of excess heat or excess cold.

A humidity-loving, tropical or semi-

Culture

tropical bamboo

will likely suffer greatly when grown

in a dry desert environ-

ment, particularly when desiccating winds exacerbate the effect. Even though day-

time temperatures may be similar to the plant’s preferred condition,

the cool

nighttime temperatures typical of desert environments will greatly reduce the vigor and health of the tropical and semitropical bamboos. Although not generally

a concern to the American gardener, many tropical herbaceous bamboos require high humidity levels of 70 percent or more, curling their leaves or showing other

abnormal leaf movements when stressed. What constitutes an environmental stress or extreme depends on the species of bamboo.

A temperature of 25°F (—4°C) may be extreme for a tropical bamboo

such as Guadua angustifolia, but not at all extreme for a temperate bamboo like Phyllostachys heterocycla {. pubescens. Indeed, most temperate bamboos need a period of winter cold in order to grow and thrive. There are exceptions, however. Phyllo-

stachys aurea, for example, is commercially cultivated in Costa Rica and grows well without the benefit of a period of winter cold. Some temperate bamboos, such as P. heterocycla {. pubescens, thrive in climates with hot, sunny summers, there is ample

and

moisture

“mountain bamboos,”

humidity.

Other temperate bamboos,

providing notably the

such as Fargesia nitida, cannot tolerate strong sun, high

summer temperatures, or hot nights. Many chusqueas can tolerate strong sun and

hot daytime temperatures, but require cool nights for their health and survival. Wind, particularly in conjunction with low humidity, exaggerates the effects of excess heat or cold. In the Hira Mountains of central Japan, varying degrees of wind exposure help shape the growth of Sasa tsuboiana. Where the wind is strong, the bamboos grow more densely, but are less tall, and longevity is decreased. Like most plants, bamboos generally prefer conditions free from saltwater in the soil or air. Some species, however, are reportedly quite tolerant of saltwater exposure and do well even when planted near coastal beaches. These include Pseudosasa japonica, Pleioblastus hindsii, P. gramineus, P. linearis, and P. simonii. Semiarundinaria fastuosa, S. okuboi, S. yashadake, as well as some of the hardy chusqueas, which are also reportedly relatively tolerant. In general, phyllostachys are less tol-

erant of saltwater, but Phyllostachys aurea, P. bambusoides, P. bissetii, and P. vivax are reportedly among the better.

Pests and diseases

Bamboos in the tropics are under constant assault by a rich spectrum of insects, including various borers, defoliators, and sap suckers. They threaten the plant from the developing seed through the harvested and cured culm. Fortunately, for the

103

104

Chapter

3

American gardener, the threat of bamboo pests and diseases is generally minimal and usually confined to disfigurement or moderate damage. Even those growing bamboo commercially on acreage, for the most part, suffer minimal risk. In his 1992 work describing the risks to bamboo plantations in India, Tewari cites the threat of devastation by rats, deer, livestock, porcupines, rabbits, squirrels, and goats, but adds

that the greatest risk comes

from

humans,

monkeys,

and

ele-

phants. In suburban America, the latter are of little concern, except for the risk of humans,

perhaps in the form of fraternity brothers acquiring decorations for a

tropical-theme kegger (a documented source of devastation). Aphids. In the tropics, aphid infestations can weaken and kill new shoots. In

the United States, aphids are not a significant threat to the health of bamboo, but their excretions foster an unsightly, black, sooty mold. Aphids are not robust and can be killed easily, but their ability to regenerate populations at a stunningly rapid rate makes control problematic. Without mating, they are capable of producing live young that can, in turn, reproduce again within a week. Natural predators, such as the ladybug, can be obtained from commercial supply houses and introduced in large numbers, but they will generally disappear along with their food source, allowing reemergence of the aphid population. Aphids are also active and happily building their populations both early and late in the growing season, times

when their natural predators are scarcely present. In some parts of the country, during late fall, when

neither the energies of the gardener nor the weather lend

themselves to keen vigilance, the aphid’s desecration is at its peak, decorating the leaves with the sooty black muck that remains prominent until the leaves are refreshed the following spring.

Soap sprays and chemical sprays are effective in controlling aphids. Simply spraying periodically with a strong jet of water will also help keep the aphid population in check. Persistent chemical sprays should be avoided if natural predators are to be a part of the control regimen. A combination of control methods is often desirable, aiming for suppression rather than eradication.

Beetles. In preparation for the coming season of shooting and culm growth, tropical bamboos store energy reserves in their culms in the form of starches. These accumulated starches are highly attractive to the dreaded powder post beetle in harvested culms. Traditional cultures learn to harvest the culms when the starch content is lowest. Some bamboos are inherently higher in starch than others, and thus inherently more vulnerable to attack. Except perhaps for areas like

Culture

Hawaii or southern Florida, powder post beetles are of little concern in most of the United States.

Earwigs and other leaf-eating insects. Earwigs, thrips, and other leaf-eating insects can damage tender new leaves as they are about to unfold. As the leaves mature and toughen,

the threat of damage

lessens considerably. Even on young

leaves, however, damage from these insects is usually trivial. Mealybugs. Mealybugs are warm-climate aphid relatives. An infestation may appear as cottony deposits. The powdery wax coating that gives them their name also makes them somewhat

resistant to insecticides. Soap sprays, chemical sprays,

or simply spraying with a strong jet of water will help keep the population in check. Natural predators, such as green lacewings, can be used to control them. Mealybugs are more unsightly than threatening. Mites. Mites are tiny arachnids. For bamboo growers, the severity of mite problems ranges from a never observed hypothetical to a dreaded scourge with associations akin to that of a social disease.

A dozen or more species of mites can

afflict bamboo, including the two-spotted spider mite (Tetranychus uriticae), but in America, only one, the bamboo

mite (Schizotetranychus celarius), threatens perva-

sive disfiguration and impaired photosynthetic capability. Heavy mite infestations can diminish the vigor of the plant. In China, a heavy mite infestation reduced the following year’s shoot harvest by approximately

180 lb. per acre (approximately

200 kg per hectare). The bamboo mite prefers some bamboo species to others, thriving on Phyllostachys, but also finding

a happy

home

on species of Sasa, Indocalamus,

Fargesia,

and Pseudosasa, among many others. Bamboos with densely pubescent lower leaf surfaces, such as Semiarundinaria okuboi, are highly resistant to mite infestations. Members of the same genus without densely pubescent lower leaf surfaces, such

as S. fastuosa, are readily afflicted by mite infestation. The bamboo

mite inhabits leaf sheaths for eight to ten months,

and then

emerges in the spring to infest foliage leaves. Bamboo mite colonies form a white protective web on the underside of foliage leaves. Individuals with keen vision can observe the tiny mites moving about within the web, but a magnifying lens

may be required to see them. The mites feed by sucking fluid from the leaf cells and assimilating the sugars and proteins, leaving large yellowed areas on the leaf to mark their progress. On bamboo with pronounced leaf tessellation, such as

105

106

Chapter

3

Phyllostachys, the infested leaves have pronounced rectangular areas of yellowing.

As the colonies prosper and expand,

more and more of the leaf area becomes

splotched with yellowed rectangular sections, eventually covering all or a major portion of the leaf, if conditions are favorable. The mites migrate to other leaves, similarly afflicting them. As the mites feed, they eliminate exce relying on evaporation

s water by exuding it from their bodies,

to assist in the removal process. High temperatures and

low humidity greatly speed evaporation and help mites thrive and spread rapidly. Studies of a species related to the bamboo

mite showed

that the mite doubled its

population in only 36 hours in a high-temperature, low-humidity environment. Under ideal and unchecked conditions, an infestation can rapidly afflict an entire

grove, yellowing all the leaves, impairing growth, and destroying aesthetics. Although photosynthetic capability is impaired, the bamboo’s survival is very rarely threatened.

Degraded aesthetics and, for commercial

nurseries, loss of value are

the principal concerns.

An insignificant or unknown many

parts

States,

bamboo

mites are a plague in other areas.

Regions

with warm,

the West

of

the

United

problem in

dry summers,

such

as much

of

Coast, are most affected. Regions

with humid summers,

such as much of the

East Coast, are less affected. Yet, once resident in an area, the mite will persist, waiting for a hot, dry spell to become rampant. As bamboo is bought,

sold, and traded, the mite spreads

to previously uninfested sites and may thrive and

spread

further

if conditions

are

hos-

pitable. Once established, the bamboo mite is extremely

difficult

to eradicate

completely.

Their webbing helps protect the mites from predators,

climatic

extremes,

and

contact

sprays. If only a few survivors or eggs escape eradication, the population can quickly regenerate during a period of hot, dry weather. Insecticidal soaps, sometimes in combina-

Mite damage on Fargesia leaves.

tion with oil sprays, can be somewhat effective in controlling bamboo

mites,

but both

Culture

soaps and oils can cause severe damage to the foliage and even to new branches and culms, particularly during warm, sunny conditions when control and eradication are most urgently needed. Some advocates suggest spraying with insectici-

dal soap during a cloudy day, then washing off the soap after a period of several hours. The threat of damage to the plant may be alleviated, but the degree of mite eradication remains less than optimal. So far, predator mites have proven only partially effective, but more trials are warranted.

In Japan, the bamboo

mite is reportedly only a minor pest, perhaps

held in check by Typhlodromus bambusae, an aggressive predator mite that is not native to America. On a small scale, afflicted leaves can be removed by hand, but the likelihood of leaving some mites behind is high. In certain situations, removal of all aboveground growth and burning or careful disposal of the debris may be an effective, though radical approach. A systemic miticide, to the extent that any effective ones even exist, would likely be inappropriate if one intends to harvest shoots for the table. A miticide that is absorbed into the leaves but does not migrate throughout the plant is arguably for control and eradication. The miticide is absorbed

the best mechanism

by the

leaves and then kills the mites as they feed. Additional applications at periodic intervals may be necessary to kill subsequent Some

miticides

are

ineffective

against

eggs,

against eggs, but less effective for live mites.

generations of mites as they hatch. whereas

others

A successful

may

regimen

be effective may

include

periodic application of a single miticide, or application of two different miticides, or application of a persistent miticide. The availability and legality of the different miticides varies widely. Check

local sources for what

is available and permissible

for your area. Total eradication may be possible if one has only a few, small plants, but if one has large plants, or a grove, total eradication may not be a feasible goal. Rampant infestation can reoccur if even a few mites or eggs are allowed to remain. For most gardeners in mite-afflicted areas, ongoing, periodic treatments are inevitable. Many bamboo nurseries, resigned to the inevitability of some level of infesta-

tion in their primary groves, isolate the containers of bamboos that are for sale and treat them thoroughly for mites. This is a good practice for all who intend to trade

or sell bamboos to others. If you live in an area where mites are a problem, or if you

obtain

a new

bamboo

plant from

such

an area, the plant should

be tem-

porarily isolated and treated for mites. Only after the new plant is proven mite free should it be removed from isolation.

107

108

Chapter

3

Scale. Scales are aphid relatives that typically appear as bumps on the culms and branches of semitropical and tropical bamboos. They are unsightly, but generally do relatively little harm. Winter chill usually eliminates them, and they have many natural predators. Their exterior armor makes them resistant to insecticides except when immature. Mature scales are immobile. Scales can be picked off or scrubbed off with a plastic scouring pad.

Slugs and snails. The tough, unappealing culm leaves protect young culms from slug and snail attack, but as soon as the culm leaves drop away, the young

culms are vulnerable for the short period of time before they harden sufficiently. Although

rarely a significant problem,

a new culm

disfigured by a slug or snail

can be an unpleasant surprise. Bamboo seedlings, however, are vulnerable and can disappear in a single night’s rampage. The standard garden remedies for these pests apply to the protection of bamboo as well.

Sooty mold. An unsightly mold that forms a black coating on leaf surfaces, sooty mold lives on the secretions of aphids and related insects, thriving in cool, moist conditions. The mold blocks light from reaching the leaves, thus diminishing photosynthesis. It is controlled by controlling the sucking insects that provide the secretions it feeds upon.

Mammals.

Various mammals

pose a potential threat to bamboo.

Bamboo

shoots and foliage are attractive food sources for many animals, but circumstances vary, and the same mammal

may present a major threat in one situation and no

threat at all in another. For some mammals, such as mice, chipmunks, squirrels, and deer, eating bam-

boo is a learned response. When

I introduced bamboo to my suburban neighbor-

hood by planting it around my home, the ubiquitous gray squirrels did not bother

the new shoots. Presumably, casual exploration led the squirrels to discover that the new shoots were worth gnawing. Now that the pattern has been learned, new

shoots and young culms are threatened each spring. Some growers report severe problems with deer that eat foliage as well as new shoots, yet other growers report the presence of heavy deer populations in and around their groves, but no deer damage to bamboo. Voles and gophers can cause major damage at or below soil level, sometimes eating tender new shoots and rhizomes before they emerge from the ground. Voles, sometimes called field mice or meadow mice, are especially vexing in some

Culture

areas. Unfortunately, thick mulches, generally beneficial for bamboo,

only help

shelter and encourage the beasts. Other mammals may also be sources of damage. Even dogs and cats have been known to chew on new shoots and culms, and their scratching and digging can cause

inadvertent damage.

Livestock

usually

regard

bamboo foliage as a highly desirable browse. Although not likely a problem in Boston or the suburbs of Los Angeles, kangaroos and

wallabies

can

decimate

new

shoots and leaves. Giant pandas consume

growth between

with

their penchant

two and

for new

four metric tons of

bamboo each year, but they too are seldom a problem in the American residential garden.

Different control methods may be appropriate depending on circumstances. They include providing ready availability of a preferred food source; commercial repellents that are painted or sprayed on new shoots and young culms; shavings from aromatic deodorant soaps that are scattered about or hung from branches; hunting and trapping; poisoning; sound generators for the air or ground; fencing; wire or plastic screens for individual shoots; and underground

mesh or surround-

ing gravel trenches for tunneling animals. In some instances, methods can be combined to control the spread of bamboo as well as damage to it. A fence separating livestock from a bamboo grove, for example, keeps the livestock from the grove, while effectively limiting unwanted spread of the grove as the livestock consumes the new shoots and foliage along the fence line.

Buying Bamboo Those who

live in the heart of bamboo

country have the best choices of sources

and methods for obtaining bamboo. Extensive selections of bamboo are available through specialist mail-order nurseries, however, so even individuals without a local source can still enjoy the beauty of this exotic plant.

Quantity and spacing

Quantity and spacing guidelines can only offer a basis for decision. The question, “How many plants do I need?” elicits the return inquiry, “How big of a hurry are you in, and how much do you want to spend?” The number of plants that should be purchased to fill an area is a basic infor-

mation need that does not lend itself to a ready answer. The type of bamboo, grow-

ing conditions, and the goals of the grower are all factors. If rapidly establishing a

109

110°

Chapter

3

hedge is the principal goal, and the extra cost of additional plants is not a limiting factor, then plant spacing of 2 to 3 ft. (0.6 to 1 m) may be desirable. If the grower can wait an additional season or two, growing conditions are optimal, and bamboos with a diffuse growth

habit are being planted, then spacing of 6 ft. (2 m) or

even more might be reasonable. Ornamental groundcover bamboo is typically planted at a spacing of 1 to 3 ft. (0.3 to 1 m), but like planting for a hedge, the plants may be spaced much further apart if the grower prefers to save costs and wait the extra seasons. A small grove of medium

to timber-sized leptomorph bamboo can be effec-

tively started with plants spaced at 6 to 10 ft. (2 to 3 m). would

A commercial grove

typically be planted with a wider spacing. Experiments

in Alabama

con-

cluded that a spacing of 15 to 20 ft. (5 to 6 m) for small nursery plants was satis-

factory for establishing

a commercial grove over

10 to 15 years, and that little

would be gained by closer spacing. By definition, semitropical and tropical pachymorph

bamboos

with a caespitose habit spread slowly. One might think that a

much closer spacing would be desirable to more quickly “fillin the gaps,” but their rhizome and root clumps are more subject to the limitations of overcrowding than leptomorph bamboos. Particularly if large, mature clumps are the goal, sufficient spacing must be allowed so the gradually expanding clumps do not crowd each other and their expansive root system has room to develop. Because each plant develops its own system of rhizomes, roots, and culms, which requires a decade or so to fully mature, radically increasing planting density

does not establish a mature grove that much

more rapidly. However, since the

grove’s canopy helps create its own beneficial, moderating environment, provides its own carpet of mulch, and so forth, there is some benefit in planting somewhat more densely to create this environment more quickly. Plants that are larger than common

nursery stock will fill the gaps faster and more rapidly establish mature

rhizome and culm systems, thus reducing the time to grove maturity.

Other factors can also affect decisions on planting density. For example, if the grove will be harvested prior to achieving full maturity, it may be desirable to in-

crease the planting density so that the gaps between the plants are filled by the time of the first anticipated harvest. Some applications require an “instant landscape,” in which no time is allocated for development and growth. The plants are installed like pieces of turf (which they essentially are), abutting each other. Most leptomorph bamboos, whether dwarf or timber, lend themselves to such treatment,

creating

an

instant

ground

carpet,

screen,

or grove.

Culture

Sources The American Bamboo Society (ABS) produces a yearly list of all species and forms of bamboo for sale in the United States, including brief descriptions, names and addresses of the bamboo

nurseries that sell them, and notes on whether the plants

are available by mail or locally. New members automatically receive a copy of the listing. The listing is also available on the ABS -org/abs/,

For membership

information,

web

site at http://www.bamboo

see the ABS

web site or the section on

the American Bamboo Society in chapter 7 of this book. Bamboo plants are available in a wide range of sizes from a variety of sources. Larger plants are often available from local bamboo

nurseries.

An

extensive selection

of species and

nurseries and non-specialist

forms are available

by mail

through specialist bamboo nurseries, but the plants are necessarily smaller than what might be available locally. Local nurseries. The bamboo

plants available through

eries are typically the more commonly

non-specialist nurs-

available varieties, such

as Phyllostachys

aurea (golden bamboo), or a generic groundcover bamboo, often a species of Pleioblastus, sometimes generically labeled Sasa pygmaea, Arundinaria pygmaea, or perhaps

even

labeled

(sometimes

correctly)

Pleioblastus pygmaeus.

Prices at non-

specialist nurseries are often substantially higher than prices at specialist bamboo nurseries. A search of non-specialist nurseries can, nevertheless, be worthwhile.

Although the more commonly available bamboos may be of less interest to the hobbyist or collector, they are still beautiful and rewarding plants. A much greater variety of bamboo may be available through local bamboo nurseries. Groundcover and small bamboos are commonly sold in 1- or 2-gallon containers. Medium-sized and timber bamboos are typically sold in 3- to 10-gallon containers. Ideally, the plants will be large enough to immediately look good in the landscape, sufficiently robust to rapidly generate new growth, and small enough

for relatively easy vehicle transportation. Some bamboo nurseries spe-

cialize in large specimen plants and can deliver and install them as part of their sales and service. Although a single timber bamboo seedling can eventually produce a towering forest, several decades

may

plants may still require many

grows

very rapidly, but small

years to fill a landscaping

need. If cost and trans-

be required.

Bamboo

portation concerns are not prohibitive, larger plants can have an immediate landscaping impact and may be capable of generating substantial new growth.

111

12

Chapter

3

Local nurseries may also sell field-dug plants wrapped in burlap. If plant quality is good, this can be an economical way to obtain many

new plants for rapidly

establishing a grove or large landscape planting. Mail order. Mail-order bamboo nurseries are excellent sources for acquiring less common

or hard-to-find species and forms. In general, however, the plants

are smaller, and when shipping is added, the prices may be higher than

for locally

purchased plants. For the hobbyist or collector, or where bamboo is not readily available locally, mail-order nurseries are

a welcome source.

Because some destinations require plants to be shipped soil free, some nurseries may ship all plants without soil. Plants shipped in this manner weigh less, but are less stable than plants shipped in the same container and soil in which they have been growing.

Plants acquired

from mail-order nurseries cannot be exam-

ined and evaluated before purchase. The nursery’s reputation and past experience are the only guides to quality. As might be expected, some nurseries are better than others. I have purchased many excellent plants from mail-order nurseries and have only occasionally been disappointed in the quality of the material. Sales and auctions. The American Bamboo Society and its local chapters hold bamboo auctions and sales. Species new to the United States and other less com-

mon bamboos are often first available at the auctions. The plant sales are a good place to find a wide variety of bamboos at a moderate price from enthusiastic and

knowledgeable growers. Plant sales are also an important source of revenue for the American

Bamboo

Society and its chapters,

funding new bamboo

introduc-

tions, publications, workshops, and research.

Evaluating plants for purchase When buying plants locally, careful examination will help you choose the best stock. For best growth potential, the rhizomes, roots, culms, and foliage must be in balance. If one element is weak, new growth will be diminished or delayed. Appearance. Unlike many other plants, the current aesthetics of a bamboo plant are much less important than its ability to generate new growth. A tree, for example, generally retains its basic shape for many years, perhaps throughout its

life. When purchasing a tree for the landscape, its shape and aesthetics are a prime consideration. New bamboo culms, however, are generated every year. In a developing grove, the new culms will be larger and more attractive than the previ-

Culture

ous year’s culms. Older culms are periodically removed from the grove. In most instances, a buyer will want to choose a bamboo plant based on growth potential rather than current aesthetics. Ideally, of course, a plant with maximum growth potential that also looks good is the best of all. Rhizome and root system. If feasible, look at the rhizome and root system. Particularly for leptomorph bamboos, but for pachymorph bamboos as well, the rhizome system is an excellent indicator of potential growth. Large, vigorous rhi-

zomes with a healthy creamy yellow coloration (where not covered by sheathing) and similarly colored, healthy, bright creamy yellow buds indicate a robust plant capable of generating vigorous new growth.

Healthy buds look bright and plump;

avoid plants with rhizomes and buds that are dull brown. Plants with a large, vig-

orous rhizome system will be capable of generating larger and more numerous culms, and supporting the dramatic growth for which bamboo is known, whereas a plant

with

a feeble rhizome

system

will be incapable of generating

vigorous

growth. Beware of large culms with small rhizome and root systems. These plants may be newly dug, less stable, and incapable of sustaining growth commensurate with

the size of the existing culms. On the other hand, the larger culms may be immediately useful in the landscape. weeks or more and

If the plant has been in the container for several

looks healthy, it may

be a good choice, depending

on cost,

buyer needs, and expectations. For leptomorph bamboos, a root ball that fills the container, and rhizomes circling the perimeter, indicate a plant that is well estab-

lished and easily capable of sustaining existing culms and generating vigorous new growth. If soil readily falls away and

rhizomes,

the bamboo

from the roots may

have been

recently dug and potted. Such a plant may be excellent stock, but its stability will not yet have been established. Keep in mind, however, that some soil mixes for container bamboos

are purposely

coarsely

textured

and

Right: A healthy, vigorous, bright creamy yellow rhizome bud. Dull brown rhizome buds are usually not viable and are incapable of generating new growth. This healthy rhizome bud has already begun shooting.

114

Chapter 3

loose. This type of soil will have a tendency to fall away more easily even for es-

tablished plants.

Culms. Look at the culms, particularly the newest ones. A large, field-dug bamboo may have impressive looking culms, but its rhizome and root system may be incapable of generating culms of equal size. New shoots or culms that have been generated since the bamboo was potted show the plant's current capability.

New, fully extended culms are the best indicators. A shoot with an impressive diameter may not develop fully if the reserves in the rhizome system are exhausted before growth can be completed. If this is the case, the shoot may abort and not develop into a culm (also common and normal in established groves for some of the later emerging shoots) or the culm may have compressed internodes and rapidly taper to a short final height. If new growth is modest or weak, look for a better plant. Judging the capability of a bamboo plant is easiest after the bamboo has been potted and the period of new culm growth has been completed. If the ability to generate new, vigorous growth

is paramount,

seek out plants that have gener-

ated the most vigorous new culm growth since the plant has been potted. In this context, the size and number of the older culms is largely irrelevant, unless they fulfill an immediate landscaping need.

Foliage. If a plant is being selected for its growth potential, foliage is much less of a concern than the rhizome system or the number and vigor of new culms, but

as the energy-generating mechanism

for the plant, foliage leaves should not be

completely ignored. Rhizomes (and culms, particularly for pachymorph bamboos) are the food-storage repositories that make the intense period of dramatic culm growth possible, in addition to fulfilling other immediate needs of the plant, including the generation of new foliage leaves, but it is the foliage leaves that generate the food and energy for ongoing needs and for storage of any reserves. Usually, adequate foliage comes automatically with the other factors in the selection process. For example, if a plant is selected because of its many vigorous new culms, a vigorous and extensive foliage canopy is already assured. For maximum growth potential, if there is a choice between two plants with equal rhizome systems (and new culm growth, depending on the season), choose the plant with

the most leaf area. If an immediate

landscaping need must be met, however,

a different choice

may be warranted. For example, if one plant has the most foliage area, but is bushy

Culture

in form, and a statelier look is immediately needed, a taller plant may be a better choice even though it may have less leaf area.

Inability to generate new growth. Although uncommon, particularly when

purchasing from reliable sources, it is nevertheless possible to have a healthy look-

ing plant that is incapable of generating new growth. One typically encounters this when a bamboo plant has been propagated, and the propagule does not have viable rhizome buds to generate new rhizomes or culms. If the shooting season is over but no new culms have been generated, the

plant may never be capable of generating new culms—or the plant may still shoot late in the current season, or may be directing growth to the rhizome and root system. In any case, the plant is, at best, diminished in its ability to generate new growth rapidly, and a different plant should be selected, if available.

Examine the rhizome system for plump, bright creamy yellow buds that indicate the ability to generate new growth. A new rhizome also indicates that the plant is viable and will be capable of generating new culms during the next shoot-

ing season (or, sometimes, delayed culms during the current season). If both the

shooting season and the season for new rhizome growth

have passed, and there

are neither new culms nor new rhizomes, avoid the plant. It may never be capa-

ble of generating new growth.

Harvesting Harvesting shoots Harvesting methods vary widely. Ideally, one would employ a method that would, with the most rapid speed, least effort, and without waste or damage, garner the highest quality, best tasting shoots. In practice, these elements are somewhat in conflict, and some degree of compromise is required. Speed is clearly a factor if one

is harvesting a grove commercially. On the other hand, if you are a gardener and have decided to “sacrifice” a precious shoot or two for your table, high-speed harvesting methods are hardly a concern.

So, when and how should you harvest a shoot? Shoots become increasingly tough and less sweet tasting the longer they are out of the soil and the taller they grow. The better bamboos for shoot harvesting are excellent when young and ten-

der, and they still remain good even if they are somewhat tall or have been out of the ground for some time. The least good species are marginal from the start, and

stretching the limits with them will not likely result in a fine culinary experience.

115

116

Chapter 3

Some cultures, however, prefer astringent shoots for some cuisine, so in this con-

text, the preferred species and harvest times would be different. The maximum preferred shoot

height

for tender, sweet

shoots is not a constant but is propor-

tional to the diameterof the shoot. Yet, a strict ratio of height to diameter is not appropriate either, as what would be a suitable ratio for a tiny shoot would be out of

line for a giant timber bamboo. For the commercial producer, economics plays a role in determining when to harvest, since yields are higher when harvest is delayed. When harvesting shoots from the garden or landscape, compromise is also the rule, balancing quality with yield.

For practical

purposes,

shoots are typically

harvested

after they

have

emerged from the ground, but before they are out too long and have toughened. If a new shoot would provide a desired new culm for expansion or increased density of a screen or hedge, it may be best to resist its role at the table. On the other hand,

smaller

shoots,

or

those

that

appear

where a culm is not needed in the landscape, are excellent candidates for harvest. The best way to get a feel and understanding for harvesting shoots is to do it. As a very broad

rule of thumb, unless you are harvesting giant timber

bamboos,

harvest

shoots

when

they

have been out of the ground for no more than

a week or so, and when they are no more than 8 in. (20 cm)

tall (preferably shorter). This is

just a starting point.

Explore

freely with

the

species in your grove or garden. Sometimes, premium emerge

shoots

are

harvested

from the ground,

before

they

or soil or mulch

is

mounded on top of the emerging shoot to keep it “in the ground”

longer. These

may

be re-

garded as specialized techniques, rather than general harvesting practice. Shoots grow rapidly and should be checked often

ES

Rat 8 ac APhyllostachys vivax shoot ready for harvest.

i”:

to make

sure they are harvested

at the

optimal time. If you are harvesting a grove, the shoots should be checked and harvested daily, if possible. Shoots can be harvested

by grasp-

ing the shoot at its very base, penetrating the

Culture

soil with your fingertips slightly, then rocking the shoot back and forth and twisting a bit until the shoot snaps free. Although this works well enough, some of the edible portion of the shoot is left behind. Severing the shoot below

ground to get

more of the edible portion is usually a better idea. If the shoot is small, a knife, a sharp digging tool, or other similar instrument

can be used.

Except

for the pro-

tective culm leaves, the shoot should be quite tender. I have used a cheap, stainless steel kitchen knife for the purpose, as well as a sharpened cultivating knife of the kind that is sold at garden stores for digging in the soil. The shoots of pachymorph new

bamboos

culms.

are generally severed just above the buds that will produce the

Leptomorph

bamboo

shoots

should

be severed

at the base of the

shoot, above the neck, where the flesh is tender and not tough. Larger shoots are best harvested

with tools that one uses standing up, using

two hands and possibly a foot to plunge the tool into the soil. This is also the preferred method

when

speed in harvesting a

grove is a factor. In traditional bamboo shoot harvesting

cultures,

the

tool

may

take

the

form of a rectangular blade that is a linear extension of the handle, or a narrow triangular blade

affixed

similarly.

A narrow,

western

garden spade with a square blade is an alternative.

Narrow-bladed

tools

that

can

be

plunged into the soil are particularly useful with tightly clumping pachymorph bamboos, where the digging space may be quite confining. Another

traditional alternative

hoe-like tool with a long narrow

is a

blade. This

is best suited to leptomorph bamboos where there

is sufficient

space

to dig, and

where

damage to nearby rhizomes and buds is less of a threat.

See the section “Eating Bamboo” in chap-

ter 6 of this book for information

on how

to

prepare shoots for the table.

Harvesting culms Culms should be harvested with a saw, never with a hatchet or ax. A hatchet or ax will

A large Dendrocalamus asper shoot. Quail Botanical Gardens

118

Chapter

3

damage

the culm

that is being harvested,

risk damage

to nearby culms and

rhi-

zomes, and leave jagged stubs that are unaesthetic and threaten injury. The culms of leptomorph bamboos should be sawed, flat across, near their base, minimizing “stumps” that are not only unsightly, but also troublesome or even dangerous protuberances that can trip a worker or damage machinery. To guard against rot, culms of tropical pachymorph bamboos are usually sawed higher, always above a node, at up to 8 in. (20 cm) or more above ground. Any medium- to fine-toothed saw is suitable for the task. Very narrow blades work well when the culms are crowded close together, but the narrow blades tend to bend and kink more easily. Somewhat wider blades are preferable when one has the space to use them. There are many schemes for determining the proportion and age of the culms

to be harvested. In general, clear-cutting is not recommended

for either pachy-

morph or leptomorph bamboos, as it weakens the bamboo and inhibits re-growth. In Orissa, a state in India where clear-cutting Bambusa bambos is a common

local practice,

the groves are incapable of producing fullsized culms again until

10 years after clear-

cutting, a significant loss of productivity (Tewari

1992). Culms less than three years old

should not be harvested when quality culm wood

is desired.

For some bamboos,

addi-

tional age, up to seven years or so, may yield even stronger culms. vesting

practices

Most

target

commercial

culms

that

har-

are not

much more than three years old. Although culms can be taken at any time

during the year, some seasons are better than others. In traditional cultures, harvesting regimens have evolved based on practical expe-

rience with native bamboos. In Java, culms are harvested

in the “old season,”

a period

roughly corresponding to the months of January through June. During this period, particularly in May, the starch content of the Javanese

Dendrocalamus giganteus. Quail Botanical Gardens.

bamboos

is at its lowest. This is im-

portant for two reasons. The dreaded powder post beetles are less likely to attack the culms

Culture

when

the starch content is low. Secondly,

the new

culms,

having depleted the

starch reserves in the mother culms for their rapid period of growth, are no longer dependent on the (now nearly nonexistent) energy stores of the mother culms. If

the mother culms were harvested during the shooting and growth period, energy stores would be diminished, and growth would suffer. In general, the culm harvest period is more critical for tropical pachymorph

bamboos than for temperate leptomorph bamboos. The tropical bamboos are at great risk of powder post beetle attack, and bamboos with a pachymorph rhizome system are generally more dependent

on starch reserves in the culms to support

new growth; leptomorph bamboos have a network of rhizomes for energy storage.

Bamboo culms are best harvested after the period of new growth has been completed. Leptomorph bamboos have a period of rhizome growth that follows culm growth. For most leptomorph bamboos, the period of rhizome growth ends in late fall, the time when the culm harvest usually begins. Methods for curing bamboo culms are quite varied. Before drying, tropical bamboos are sometimes submerged in water to remove as much starch as possible and reduce the risk of powder post beetle attack, and the culms may be subject to a variety of chemical preservative processes. Such measures are of little concern in

most of the continental United States, but may be germane to gardeners and growers in Hawaii and southern Florida. To assist the drying process, the leaves can be left on the culm until they wither. Experiments have shown that, as the culm dries and cures, it loses 4 to 16 percent in wall thickness and 3 to 12 percent in diameter (Tewari 1992). The culms

should be stored so that they are not bent by their own weight.

Lg

CHAPTER

4

Propagation

SOME FORM OF VEGETATIVE PROPAGATION is generally the method of choice for establishing and distributing bamboo plant materials. Since most bamboos flower infrequently and unpredictably, one cannot simply buy a packet of seed from the neighborhood nursery. The millions of acres of Phyllostachys heterocycla {. pubescens forests provide readily available quantities of seed in China, but for practical purposes, in most places and for most bamboos, it is not possible to obtain seed on demand.

In fact, many decades may pass before seed for a particular bamboo

becomes available. In most instances, ongoing commercial

propagation

of plant

stock from seed is not only impractical, but also impossible. Growing bamboo from seed may be a necessity, however,

to replace a grove that is weakened

or dying

from flowering. This is most prominently a concern for pachymorph bamboos.

Propagating from Seed Although propagation from seed is a serendipitous method that cannot be relied upon as a predictable source (except for the few bamboos that flower annually or continuously), it nevertheless can be an occasional windfall source of numerous small propagules and can provide the opportunity to obtain interesting variants that would be impossible with the normal means of vegetative propagation. Seed propagation plays a role in developing selections with desirable characteristics for future vegetative propagation. For the gardener, there is something special and

120

Propagation

magical in growing a plant from seed, whether it is a garden vegetable, a tree, or

bamboo. Since bamboo seed is so rare, the opportunity to grow bamboo from seed is all the more special. | find it very satisfying to grow bamboo from seed and am always glad when the opportunity is presented. In general, bamboos exhibit significant polymorphism, and openly pollinated wild plants often show considerable diversity in the plant material generated from

seed. The degree of polymorphism varies, as some species are quite stable, exhibiting little variation in seedling populations, whereas others exhibit significant variation. From the standpoint of survival and evolution, polymorphism helps ensure continuous adaptation in response to changing environments. Apart from varia-

tions in gross morphology and readily observable characteristics, molecular markers in DNA, enzymes, and metabolites reveal polymorphic variations that can be correlated with characteristics not readily apparent in seedlings, thus offering the prospect of greater refinement in the selection of desirable propagules—at least in

the research and development laboratory, if not for the average gardener. The flowering of bamboo is not a guarantee that viable seeds will be produced. For example,

Phyllostachys heterocycla {. pubescens, which

flowers at intervals of

about every 50 to 60 years, has a pollination rate of less than 10 percent. It is wind pollinated, but its flower structure is such that it pollinates only with difficulty. Broadly speaking, Old World pachymorph

bamboos ripen about

15 to 30 days

after pollination, whereas leptomorph bamboos, such as P. heterocycla {. pubescens, take longer, from

50 to 70 days (Tewari

1992). When

ripe, the seeds fall to the

ground. Reportedly, a few bamboos, such as some Sasa and some tropical herbaceous bamboos, may take up to a year to germinate. Seeds from one species of Fargesia remained

viable after five years in the soil. Some

Himalayan

bamboos,

among

others, have a dormant period and may require a period of cold before germinat-

ing. Himalayacalamus hookerianus seed, for example, needs a dormant period of one to eight months under temperate conditions before germinating, although a period of cold may reduce the dormant period. The preceding germination behaviors are more exceptions than they are the rule, however. Most bamboo seed has no dormant period and maintains viability less well than common seed grains. Without special measures, some seeds must be afforded the opportunity to germinate in the same year they are produced, otherwise germination may not occur. Generally, bamboo seeds germinate within two to three weeks. Chusquea coronalis, a species with very small seeds, can germinate in less than a week. Fresh seed germinates more quickly than seed that has been

121

122

Chapter 4

seed can be harvested and germinated even if the surrounding bracts are still green and the seed is still tightly affixed, but as a general rule, seeds are mature and ready for germination when they can be shaken from

stored. Some

bamboo

the plant. At maturity, the germination rate of Phyllostachys heterocycla f. pubescens is about 50 percent, dropping to as low as 10 percent within six months. At eight months,

if the seed is kept at room temperature, the germination rate drops to near 0 percent (Yat et al. 1984). Cold temperatures permit somewhat

longer storage with a

higher rate of germination, and special preservation methods can extend viability to more than three years. Some tropical bamboos, such as species of Melocanna, produce a fleshy fruit rather than a seed grain (caryopsis) typical of most grasses. The fleshy fruits do not lend themselves to long-term

storage,

however,

so seed

propagation from these species is even more problematic. In natural conditions, many seed are dispersed in a way that is ill suited to effective germination, and the seeds and new seedlings are subject to attack by all manner of rodents, insects, birds, slugs, snails, and other beasts of the wild. Greenhouse conditions offer a much higher rate of germination and survival. Seed propagation requirements vary among species, but as a general practice, the seed should be planted as soon as possible after maturity. The definition of maturity, in this context, means viability. Some bamboos, such as Phyllostachys, require the seed to be fully ripened before harvest, particularly if the seed is not planted immediately. The seed of other bamboos, such as Sasa, Indocalamus, and Pleioblastus, can be successfully harvested and planted even if not fully mature, al-

though the seed will retain viability longer if it is more completely ripened. In general, seed is ripe when it can be easily removed from the plant by light pressure,

bumping, or wind. Seed can be harvested by hand, or by placing a sheet or tarp beneath the plant and shaking the culms. Chaff can be removed with a hand blower or fan. For most bamboos, the soil should be a slightly acidic, loose, moisture-retaining, readily draining mixture. Commercially available potting soils suit the purpose

well, as do many self-mixed soils, such as a composition of half vermiculite and half peat moss. At planting, the seed should be covered with 6 to “4 in. (0.3 to 0.6 cm) of soil and keep moist. The pots or seed trays can be covered with transparent plastic or placed in a plastic bag. On a small scale, for even greater reliability and control, seeds can be layered in moist paper towels and placed in a plastic bag, then transferred to soil, in small pots, after they sprout. For germination, the seeds should be kept in a warm, bright environment, but shielded from intense sun-

Propagation

light or other withering light source. When the seedlings are several inches tall, they should be gradually hardened by increasingly exposing them to more natural conditions. Until they reach maturity, young plants will be more sensitive to extremes of heat and cold and should be shielded accordingly. Bamboo

nurseryman

Gib Cooper and his partners were largely responsible for the American reintroduction of Phyllostachys heterocycla {. pubescens via seed propagation. A brief summary of their propagation efforts illustrates some of the methods and results. Propagation was facilitated by soaking the seeds in warm

water for 24 hours prior to planting in a loose, humus-rich soil. At temperatures

between 68 and 78°F (20-26°C), the seeds began germinating within a week. The

first leaves appeared in 21 days. At about the time the seedlings put out their third leaf, approximately a quarter of the seedlings yellowed and died. It is speculated

that this mortality occurs at the transition from dependency on the seed to support

from the emerging root system. If the seed was not sufficiently mature or is otherwise deficient, the seed may cease providing critical nutrients before the seedling’s root system is fully ready to assume that role. Seed propagation is sometimes used in afforestation projects in China. After a year, when the seedlings are about 1 to 1/4 ft. (30 to 46 cm) tall, they are transplanted. The success rate is high, but a new grove or forest cannot be established nearly as quickly as would be the case if the propagules came from culm and rhizome divisions rather than seedlings. Keeping the seedlings in a nursery until they are 3 to 6 ft. (about 1 to 2 m) tall speeds growth, but also defeats some of the purpose and benefit of seed propagation.

Seedling variations New plants grown

from the seeds of cultivars will generally reflect the character-

istics of the type form, rather than the cultivar. Seedlings from cultivars with variegated leaves or differently colored culms, for example, will generally revert to the green culms and leaves of the type form. On the other hand,

flowering affords

the opportunity of discovering variants with properties different than the type form. Out of many hundreds of seedlings, some may display leaf variegation, unusual culm coloration, exceptional vigor, different growth habit, or any manner of

other characteristics. Sometimes these characteristics will appear in a young seedling, only to disappear as the seedling matures. In other instances, these charac-

teristics may not be apparent until the seedling has achieved some maturity. The seedlings of some species, such as Otatea acuminata ssp. aztecorum, exhibit very little variation. Others, such as species of Phyllostachys, tend to exhibit much

123

124

Chapter 4

more variation, although one may propagate hundreds of seedlings before encountering a variation of significant note, such as leaf variegation or differences in culm color. Sometimes one encounters a much greater frequency of variation— and not always for the better. I once planted a small number of P. flexuosa seeds,

and well over 10 percent of them were albinos. They were rather striking for a short time, while the seed provided the nutrients for growth, but the absence of

chlorophyll ensured a rapid demise.

Desirable variations are a matter of context. Variations may be particularly undesirable in a commercial forest, for example, and in such instances, vegetative propagation assures that new plants will have the same qualities as the mother plant. In China’s bamboo reforestation projects, variegated Phyllostachys heterocycla {. pubescens seedlings are inherently weaker performers and subject to discard, but

the betterof the variegated plants may be highly desirable ornamentals. The flowering of Fargesia murielae in the 1990s gave rise to a number of named variations, including some that were small, slow growing, and weak. Some of the named variations may be of presumptuous merit. On the other hand, a small, weak, slowgrowing cultivar might be the ideal plant for a rock garden or similar application. Seedlings of leptomorph

bamboos

tend to recapitulate a clumping habit in

their early stages of growth. Duration varies. Sasa tsuboiana, for example, rapidly displays a running habit, extending leptomorph rhizomes very early in the seedling stage and producing many new culms from lateral buds on the rhizomes. Sasa

kurilensis, in contrast, initially displays more of a clumping habit with limited lateral expansion.

Hybridization The lengthy flowering intervals of most bamboos greatly reduce the opportunities

for hybridization. The likelihood that two or more species will flower at the same time in the same location is very small and, thus, so is the likelihood of hybridization, either naturally or through conventional breeding programs. Although hybridization from cross-pollination is not easy and is out of the realm of the average

gardener, it has been successful. Chinese researchers have produced viable crosses in Bambusa,

Phyllostachys, and

Dendrocalamus.

Most

bamboos

flower very infre-

quently, but China’s extensive and widely dispersed groves, with varying flowering cycles, offer an ongoing supply of propagation material. Although

flowering

usually takes place from February through June, it can occur at any time during the year. Maintaining pollen viability while awaiting flowering of another species is problematic, though more refined storage methods ensure sufficient viability.

Propagation

Bamboos

exhibit few barriers when attempting to cross genera or species. Those that are more similar in their genetics and ecological needs hybridize most successfully, while less similar bamboos are more difficult to successfully cross. In

one trial, Bambusa pervariabilis,

a pachymorph bamboo, was crossed with P. heterocycla f. pubescens, a leptomorph bamboo. Of 12,000 flowers pollinated, only 34 seedlings were produced, and none was regarded as desirable (Zhang and Chen 1985). Other crosses have produced more promising results. A cross of Bambusa pervariabilis and Dendrocalamus latiflorus, two similar pachymorph bamboos, produced a high-yielding hybrid with long fibers ideal for papermaking. Once hybrids are selected for further development,

they can be propagated vegetatively,

thus preserving their genetic mix and desirable characteristics.

Natural and artificial hybridizations of other grasses have played a major role in their evolution and commercial

development.

Selective breeding programs

have produced high-yielding grain crops and increased food production. Hybrids of bamboo

and rice displayed widely varying characteristics, but all possessed a

strong stalk (Zhang and Ma 1991). Using molecular techniques and genetic mapping, selective breeding of bamboos and rices could one day yield a new and important food crop. Successful trials have been conducted

with in vitro induction of flowering in

several tropical bamboo species. In this process, bamboo tissue is cultured in a test tube or other vessel, then

induced

to flower. Although

there are limitations, in

vitro induction of flowering can greatly compress generational cycles, creating the

potential for the relatively rapid development of new species and forms. Hybridiz ing efforts are generally directed toward developing bamboos with enhanced commercial properties, such as greater productivity, resistance to pests,

long fibers for pulping, better taste and enhanced nutritional content of shoots, and so forth. Although variegated forms are appealing from an aesthetic and landscaping standpoint, they are regarded as weaker than the non-variegated forms and are generally eliminated during the selection processes.

Vegetative Propagation For the farmer, nursery grower, and hobbyist, vegetative propagation is by far the most common

method

of bamboo

propagation.

Several

methods

of vegetative

propagation may be employed. Each has its own strengths and shortcomings. A bamboo plant must have a viable bud to generate a new culm or new rhizome. It is possible to vegetatively propagate a healthy plant that has no viable buds,

125

126

Chapter 4

and is therefore incapable of producing new culms and rhizomes, but a fully successful propagule must be capable of generating them. Although some species of leptomorph bamboos can generate new culms from the basal buds of existing culms, the rhizome is the only permanent source of new culms and rhizomes. A propagule

that subsequently generates a new rhizome can be considered fully successful. Ifa propagule fails to produce either a new culm or new rhizome for a second year, it is unlikely that it ever will. Although

unusual,

a propagule

may

fail to

shoot for two years in a row, yet still be viable, as long as new rhizome growth occurs during that time. With care in propagation, creation of fully successful propagules need not be a concern,

unless one is forced by circumstances to use mar-

ginal material with questionable bud viability. As with other plants, somatic mutations

sometimes

occur—that

is, occasion-

ally a new bamboo culm may show characteristics that differ from the rest of the

plant it came from. If the mutated portion of the plant is propagated, sometimes the mutation

is sufficiently stable that it will survive ongoing propagation.

Al-

though quite infrequent, constant vigilance may uncover new cultivars with desirable characteristics.

Culm and rhizome divisions Propagating by division is by far the most common and reliable method for increasing bamboo stock. A culm or culms with associated rhizomes and roots is separated from an existing clump or grove. Because the new propagule is already a complete plant, the success rate of this propagation method is very high, particularly for leptomorph bamboos. Some pachymorph bamboos need a division that includes two or more culms and associated rhizomes to achieve a high success rate. Failure can occur if the foliage area is greatly out of proportion to the rhizome

and roots, as moisture is lost through the leaves. The amount of foliage that can be retained is in direct proportion to the root system and its ability to supply moisture

to the leaves. In extreme situations, all leaves may be removed, keeping the plant alive until the root system recovers sufficiently to permit the plant to send out new leaves again. The plant will regulate itself and send out new leaves in proportion to the root system’s ability to support the leaves. In such a situation, how-

ever, the balance is tenuous, and the plant must be protected from any increased

stress. The root system nearly always experiences some damage when plant divisions are taken, but recovery is relatively swift, and the root system will have significant growth in four to six weeks. Excessive foliage can be reduced by topping the culms, removing some culms

Propagation

from the propagule, pruning branches, or thinning the leaves. Excessive foliage is more likely to be a problem in sunny, hot conditions. The leaves are the plant's pri-

mary source of food, however, and the most vigorous growth is realized when the maximum possible foliage is retained. Unbalanced transpiration can also be countered with commercial anti-transpiration sprays. These treatments reduce transpiration, thereby permitting retention of significantly more

foliage than would

otherwise be possible. Bamboos treated with anti-transpiration sprays should still be kept in partially shaded conditions to prevent leaf browning. If producing the most new culms possible is the goal, rather than larger if fewer new culms, topping the propagule will encourage more shooting from oth-

erwise latent buds. Partly to ensure a stable propagule, partly to ease mobility, and partly to generate more new shoots, bamboo growers sometimes top propagules to a height of only 3 ft.

(1 m) for a 5-gallon (19-liter) container. Practices and pret-

erences vary. The propagule should be observed for signs of stress. Leaf curl in an adequately watered plant is the most readily apparent stress indicator. Remember, however, that a few bamboos normally curl their leaves in sunlight and uncurl them in the shade, so the propagule’s behavior should be compared with the normal behavior of the mother plant. If the propagule experiences only moderate leaf curl during the day and rapidly recovers at night, foliage reduction may not be necessary, un-

less the plant is expected to experience additional stress, or unless ongoing monitoring is not possible.

If the propagule is stressed and the weather is unusually sunny, hot, or windy, shade and shelter from the wind

may be warranted

until the root system of the

plant has developed enough to more adequately support the foliage. Misting the leaves, moving

the plants to a humid greenhouse

environment,

spraying the leaves with an anti-transpirant, or wetting the leaves and temporarily wrapping the foliage in clear or opaque plastic are additional methods that may be employed. If necessary, topping or partial branch or leaf removal are methods of foliage reduction that can be brought into play to balance the plant.

Although single-culm divisions require slightly more care and caution than multiple-culm divisions, success is routine, and they have the advantage of generating the most new plants from an existing clump or grove. Naturally, if size and vigor of new growth are paramount, a multiple-culm division is preferable. Single-

culm divisions usually work well with pachymorph bamboos as well as leptomorph bamboos, though a few pachymorph bamboos, such as Bambusa textilis, require a “mother and daughter,” two-culm division for best success.

127

128

Chapter

4

Ifthe rhizome and root system is proportionally large compared to the foliage area, new growth may not be as rapid, but the propagule will be in no danger of failure. Depending on the season, the propagule may attempt to balance itself by

sending up new culm shoots—or the tip of a rhizome growing near the surface may turn upward and become a new culm. Ideally, the propagule’s rhizomes should be no more than a few years old and

at peak potential for generating new culms and rhizomes. According to bamboo nurseryman Adam Turtle, with a typical Phyllostachys rhizome, about 10 percent of the buds in the first 1 to 2 ft. (30 to 60 cm) of rhizome growth from the previous summer and fall will be mature the following spring. In each of the subsequent years, an additional 30 to 40 percent of the buds will mature. By the fifth year, new

buds mature only sporadically. Propagation by division of culm and rhizome is best done just before active bud growth and the initiation of shooting. Division should be avoided during the period of active bud growth and shoot initiation and while the new culms are extending, branching, and leafing. Divisions of leptomorph bamboos can be made successfully during all other times of the year that the bamboo is not suffering undue stress. If divisions are made too near shoot initiation, the new shoots may fail to grow properly and may abort. As a general rule, it is best not to make divi-

sions immediately following the shooting period, as nutrient reserves will be depleted, and division additionally stresses the plant. However,

I routinely violate

this rule with container-grown plants with no overt negative effect.

A division from a very large plant will not be likely to support similar-sized culms the following year because of its reduced rhizome and root system. The propagule will regulate itself as necessary, and it may produce new culms that are smaller in diameter than

internodes and reduced

the mother plant, or produce culms

with compressed

height. Divisions from small to moderately large bam-

boos, however, will generate new culms that are generally in the size range of the mother plant and produce an attractive and functional propagule. Macroproliferation of bamboo seedlings is a specialized type of culm and rhizome division. At the seedling stage, both pachymorph and leptomorph bamboos exhibit

a clumping habit, forming a cluster of miniature culms, rhizomes, and

roots. Divisions can readily be made by separating the cluster into separate portions, permitting additional growth, then separating the clusters once again. With skill and familiarity, success can approach

100 percent, and a geometric increase in

the number of propagules can readily be realized. Because the multiplied seedlings are clones, they will tend to flower at the same time as the mother plant. If macro-

Making field divisions of a Fargesia species. Although a sharp-edged garden spade can be used to make the divisions, specialized tools make the task easier. Here, a section has been severed

from the perimeter of the clump by a tool affectionately known as “The Pink Slammer.”

eh The soil has been removed

thee

a

from this Fargesia division, revealing the mass of roots and rhi-

zomes. Examining the division by sight and feel, smaller divisions are identified and severed from the mass.

Propagation proliferation is carried out over a number

of years with the same clone, the time

between division and flowering decreases. Taken to its extreme, a macroproliferated plant could flower before it reached maturity

and commercial viability. For

practical purposes, this would only become a significant concern if macroproliferation from the same clone were carried out over many

years with a species hav-

ing a relatively short flowering cycle.

Pachymorph

bamboos. Creating divisions from pachymorph bamboos, par-

ticularly a mature clump of a large species with a caespitose habit, can be difficult. Short rhizomes and tightly packed clumps do not make the job of cutting away sections for propagules easy. The difficulty of breaking apart old clumps is illustrated by the occasional agricultural practice of dynamiting the clumps in lieu of

hand labor. The urban or suburban gardener, however, runs the risk of irritating unsympathetic neighbors, and dynamiting cannot be recommended practice.

Dynamiting

may

not be warranted

as a general

in any case, since the inner culms

This bamboo division has already begun to shoot, and ide-

ally, the divisions should have been made earlier. Propagating now may disturb the plant's delicate balance, possi-

bly causing the shoot to abort and the propagule to fail Note that this propagule also has a new rhizome that has not yet developed into a shoot. The propagule may also have viable rhizome buds. Even if the elongated shoot aborts, other shoots may develop.

the roots are covered with soil.

131

132

Chapter 4

and rhizomes of an old clump are generally too old to propagate effectively and significant damage is inevitable. Divisions of pachymorph bamboos are best taken from the periphery of the clump. The culms and rhizomes are generally younger at the periphery, and thus more likely to produce viable propagules.

There is also far less congestion of culms

and rhizomes inhibiting access and division. When chymorph bamboo

severing a propagule of a pa-

from the mother plant, the cut should be made at the narrow

rhizome neck. Methods vary, but the propagule’s culm or culms are typically reduced

to about 6

ft. (2 m)

in height.

Dividing large pachymorph bamboos is hardly an easy pleasure. Various methods employ a jackhammer with a blade tip, heavy-duty reciprocating saw, chain

saw, and so forth. Sometimes a tractor or a small-scale lifter are used to dig a trench around the clump and then clump to expose the rhizomes and the culm and rhizome or container-grown pachymorph bamboos, the principle

construction loader and

push or lift a side of the necks. For small clumps is the same but the exe-

cution is far easier.

Large pachymorph bamboos with long rhizome necks and a diffuse habit can also be a problem. Although congested clumps are seldom an issue, a viable division comprising a culm, roots, and a rhizome may extend 5 to 20 ft. (1.5 to 6 m) or more, becoming unwieldy at best, and certainly not lending itself to container culture. Most of the more extreme examples are tropical bamboos seldom encountered in the United States.

Leptomorph bamboos. Creating divisions from leptomorph bamboos is relatively easy. The rhizome can be severed anywhere along its length, rather than at the neck, as with pachymorph

bamboos. If the culm or culms are near the end of

the rhizome, only one cut may be needed. If the culm or culms are removed from mid-length along the rhizome, two cuts to the rhizome will be required. Divisions

can be made by plunging a sharp spade or digging tool to a depth of 1 ft. (30 cm) or so around the circumference of the area that will be the new division. The underground path of the rhizome can be ascertained by the placement of the aboveground culms, Culms emerge on alternate sides of the rhizome, and the branching sides of the culms parallel the path of the rhizome. Once the rhizome is identified,

the perimeter of the division can be extended to include more of the rhizome and its associated roots. Culms associated with rhizomes that are no more than a few years old ensure propagules with the most vigor and likelihood of producing new culms and rhizomes. Taking divisions from young bamboo on the periphery of a grove ensures that the propagules will include viable and vigorous rhizomes.

Propagation

The interior of a well-maintained, mature grove will also have many new culms with vigorous and viable rhizomes, but removal will be much more difficult

because the rhizomes intertwine to forma dense, barely penetrable mat up to several feet thick. Although the new, viable rhizomes will be closer to the top, separating them from the rest of the rhizome mat is not always easy. In these situa-

tions, choose a relatively young culm or culms, then cut through a section of the rhizome mat surrounding it, and lift out the culm or culms with the attached

“cake” of rhizomes, roots, and soil. In a thickly matted, mature grove, this task is far from easy, but specialized cutting tools ease the difficulty.

In China, afforestation of Phyllostachys heterocycla f. pubescens has traditionally been accomplished primarily by culm and rhizome division from existing forests.

Healthy, relatively short, two- to three-year-old culms are selected for propagation. Divisions consist of a culm with an attached rhizome about

30 in. (75 cm)

in

length. Although divisions can be made in fall and winter, spring division is preferable, ideally about one to two months before the start of the shooting period. The divisions are planted at a rate of about plants per hectare).

120 to 180 plants per acre (300 to 450

A “commercially mature”

producing forest is achieved in

about seven years. With this method, the new plants will be robust and stable, re-

quiring relatively little attention. Unless one happens to have a Chinese bamboo

forest for a backyard, smaller

scale growers or gardeners usually have less material available for division, but more time to attend to individual plants. Propagation methods can be modified to reflect these differences by using divisions with shorter rhizomes, and keeping greater leaf area by not topping the divisions, or by topping them less severely. More

divisions can be made

with shorter rhizome lengths, and greater leaf area

will generate faster growth. These plants will be less stable, however, and more attention is required to make sure they remain vigorous. Maintaining an adequate

balance between roots, rhizomes, and the leaf area is key to success. Curling leaves are indicators of an out of balance situation that may call for more water or shade or a reduction in leaf area by topping or trimming branches. The most critical pe-

riods occur immediately after the divisions are made and during periods of heat and drought.

Rhizomes

Propagation from rhizome sections alone, without any associated culm, is less reliable than culm and rhizome divisions. The rhizome propagules are also initially far less vigorous. Not all species can be successfully propagated from rhizome cut-

tings. Secondary factors such as soil and time of year are much more critical than

133

134

Chapter 4

in propagation by division of a culm and rhizome unit. To avoid rot, the soil must be well drained and aerated. Taking cuttings too close to shooting interferes with the new growth, but cuttings taken within one or two months prior to shooting help ensure success, since a complete plant is soon formed. Planting much further ahead of shoot initiation increases the likelihood of rot and failure. Success depends on an adequate store of carbohydrates in the rhizome system. A period of winter cold prior to taking rhizome cuttings causes greater storage of carbohydrates in the rhizomes and improves shoot growth (Adamson et al. 1978). If the rhizomes of leptomorph bamboos are pruned yearly to limit growth,

and

it is desired to use the rhizomes

for propagation

material,

pruning should be delayed until spring, ideally no more than a month or two prior to the beginning of the shooting period.

Pachymorph bamboos. Rhizomes alone are rarely used to propagate pachymorph bamboos, although it remains an option for some purposes. Observing that

small rooted shoots were growing from damaged rhizomes and rhizome fragments that were discarded after making clump divisions of Bambusa longispiculata, F. A. McClure constructed a propagation experiment using Gigantochloa apus and several species of Bambusa. Although the survival rate of the propagules was quite high, the lack of vigor and ability to generate new growth with a robust root system were apparent downsides to the method, as was the threat of rot to the rhizomes (McClure

1966).

In many instances, if one has access to a rooted rhizome suitable for propaga-

tion, one also has the option of taking the associated culm as well, topping it, but leaving some foliage, or waiting for the rhizome to develop into a rooted culm, then take the propagule at that time. Both options would offer the likelihood of in-

creased vigor and potential for more rapid growth than would a rhizome alone. However, one might choose to sever the rhizomes to make a compact propagule for ease of transportation and shipping. Also, if rhizomes are severed in the process

of creating culm and rhizome divisions, either inadvertently or because they would make the propagule too large, the rhizome pieces offer “extra” propagules. If using a rhizome alone to propagate a pachymorph bamboo, the rhizome should be less than a year old. As with leptomorph rhizomes, pachymorph rhizome propagules must have a developed root system and viable buds.

Leptomorph bamboos. The propagation of leptomorph bamboos via sections of rhizomes is far more viable and common

than with pachymorph

bamboos.

Propagation

However, not all species of leptomorph bamboos are amenable to rhizome propagation. Many

species of Phyllostachys do quite well, but some species of Sasa, In-

docalamus, and Arundinaria propagate poorly from rhizomes (McClure tomorph

1966).

Lep-

bamboos with frequent budless rhizome nodes and sparse rhizome roots

are less likely to propagate well from rhizome cuttings Culm and rhizome division is more reliable and is usually agation

method.

Rhizome

the preferred prop-

cuttings alone can rapidly generate more

propagating

material, but the propagules will be less well developed. Rhizome cuttings are effective in farming or large-scale nursery operations where covering a large area or

generating the most propagules is a prime concern,

5

A propagule is taken from the larger rhizome

iy

A rhizome section from a Phyllostachys species. The roots are less developed toward the rhizome tip. A prop-

agule taken from the tip would not be viable. The entire section can be planted in the ground, but if smaller sec-

tions are desired, only the portions with developed should be used.

Rhizome cuttings are com-

roots

section and bent to fit the container. The rhizome will be covered with soil. The normal

shooting period for this Phyllostachys species begins in about a month. If successful, the propagule will shoot and develop one or more small, bushy culms.

135

136

Chapter

4

pact and can be readily transported and shipped. Field tests in Alabama that 100 rhizomes,

indicate

12 to 15 in. (30 to 38 cm) long, will weigh about 3 to 5 Ib. (1.4

to 2.3 kg) each, and under favorable conditions, 50 percent will successfully produce new plants (Sturkie et al. 1968). For the home grower or landscaper, rhizomes provide an extra source of propagating material. One method for controlling lateral spread of a bamboo grove calls for yearly rhizome pruning. For Phyllostachys and other genera of leptomorph bamboos, the new rhizomes on the periphery of a grove lie within the first 6 in. (15 cm) of soil. Lateral spread is controlled by plunging a spade into the soil around

the circumference of the desired boundary. Any rhizomes crossing the boundary are severed and pulled from the soil. Those portions that have well-developed roots are suitable for propagating.

For the best success rate, the rhizomes should be no more than a few years old, with vigorous, well-developed roots. The rhizomes, roots, and buds should have a bright, not dark, appearance. Practical and experimental information regarding rhizome length varies, from 6 in. (15 cm) or less to 24 in. (60 cm) or more. Longer

rhizomes reduce the number of potential propagules, but with the benefit of a higher success rate and larger and more vigorous new plants. In general, growers of

nursery stock may want to use shorter lengths, particularly if the rhizomes are started in pots. Farmers planting in field conditions may tend toward longer lengths. As much as possible, the rhizomes should be oriented normally in the pot: parallel to the soil surface, with the nodal buds oriented horizontally, covered by 3 to 6 in. (7.5 to 15 cm) of soil, and mulched to protect against cold and moisture loss. If rhizomes are planted too deeply, they may rot before they are able to gen-

erate new growth. For commercial rows,

with

production,

3 to 4 ft. (1

to

1.5 m)

rhizomes can be planted end to end spacing

between

the

rows.

The

in nursery

rhizomes

and

newly formed culms are divided every one to three years. Some plant material can be left in the nursery beds. The remainder can be transplanted to pots or planted to form a clump or grove. One strategy calls for taking the plants from the original planting rows of rhizomes after the second year, leaving in the ground the culms and rhizomes that were formed between the original rows. The process is then repeated with the newly formed “row” of culms and rhizomes.

Culms or culm segments McClure

(1966)

recounts an incident

in Jamaica

when

newly

cut culms

of Bam-

busa vulgaris were placed in the ground to stake yam vines. The culms subse-

Propagation

quently rooted and formed extensive groves. The nodes of many tropical and subtropical pachymorph bamboos are capable of forming roots and generating new plants from viable buds. The Jamaican experience is an example of unintentional spread, but culms, culm segments, and even branches can be an effective method of propagation. Pachymorph bamboos. Most semitropical and tropical bamboos, such as species of Bambusa, Dendrocalamus, and Guadua, can be propagated from culms, culm segments, or branches, though not every species is equally suited to every method. Most, if not all, Old World temperate-climate pachymorph bamboos, including Far-

gesia, Himalayacalamus, and Drepanostachyum, cannot be propagated by culm or culm segments. Some species of pachymorph

bamboos, such as certain species of the

New World Chusquea, generate new plants in natural environments by layering, a reproductive mechanism that the propagator can replicate and refine. For whole-culm propagation, a newly cut culm, with or without a portion of its rooty base, is placed into a shallow trench and covered with soil. Ideally, the culm should be fairly large and no more than several years old. One or two leafy branches are left at each node and arranged to project above the soil. After several months, a root system should develop at each node. The soil is then removed from each internode, and the culm is sawed into sections, with the node and new root system roughly at the center of each section. The new propagules are left in the

ground for several more months to further develop their root system prior to transplanting. For propagating with a culm segment, a portion of a culm with one or more nodes is placed in the ground horizontally or at an angle. A small branch, sometimes with and sometimes

without

leaves,

is left to project above

the soil. This

method is effective for some, but not all, semitropical and tropical species of pachymorph

bamboos.

Dendrocalamus strictus, for example, propagates from culm

segments far less reliably than Bambusa vulgaris. Branch cuttings are successful only with certain species that have root primordia or evidence of rhizomatous swellings at the base of the branch. Such bamboos include Bambusa textilis, B. oldhamii, B. vulgaris, Dendrocalamus asper, and Gigan-

tochloa pseudoarundinacea, among many others. The rhizomatous swellings can sometimes be encouraged by removing new culm shoots generated by the mother plant (Wong 1995b).

For this propagation method, a branch, including its base with prominent root primordia or rhizomatous swelling, is cut from a culm that is no more than a few

eae

138

Chapter 4

years old. The

branch

is trimmed

to only a few nodes,

and

side branches

are re-

moved. The base is planted in the ground and the twiggy parts with leaves are kept out of the soil. The propagules are kept shaded for ten days. Roots form

within two to three weeks. Sometimes new plants are created spontaneously in nature. The root primordia develop into roots, and new plants are formed at the base of branches. McClure (1966) has suggested that some tropical bamboos that flower rarely, and do not produce viable seed, may be dispersed by a strong wind breaking away the tiny rooted plants and blowing them to a new location.

For some species, layering is a naturally occurring reproductive method. Some Chusquea,

such

as C. foliosa, C. talamancensis,

and

C. tomentosa,

have

rhizomatous

swellings at their branch bases and generate roots when brought into contact with the soil. New culms of C. longifolia have been observed to develop roots at the nodes that are in contact with the soil. Subsequently, the internodes may decompose, leaving a series of separate plants (Widmer reproductive method

1997). This naturally occurring

can be replicated by propagators. Not all chusqueas can be

propagated by layering, however. Propagating by layering is also possible, and more common,

for some arbor-

escent tropical bamboos. In this scenario, a one- or two-year-old culm at the edge ofa clump is selected in the spring. The culm is cut two-thirds of the way through, just above the ground, and then bent down

into a trench. The branches on the

lower 20 culm nodes are reduced to their second node and all the side branches are removed. The culm is covered with soil through the length of the 20 nodes. The top of the culm is left out of the soil and is cut off, except for one branch, which

is left intact and

projecting above

the soil with all its side branches and

leaves. Roots and new shoots appear within three months. The propagules are removed

the following spring.

Air layering bamboo is uncommon

and largely untested, but may prove use-

ful in generating new propagules from the branches of standing culms. In this approach, the branch nodes are enveloped in a rooting medium that is kept moist until sufficient roots form to support an independent plant. The propagule is then separated and allowed to grow on its own. Like other propagules, reduction in foliage may be necessary to bring it into balance with the fledgling root system. Although not common

for bamboos, air layering is a widespread practice for woody

plants, from bonsai to the propagation of fruit trees in China. Many air-layering variations are possible. Moist sphagnum

moss can be placed

around the basal node of a branch, and then sealed by wrapping with plastic or

Propagation

foil. The moss must be periodically checked for moisture, which can be replenished with a hypodermic

needle or other means.

In another variation, an open

container is constructed to fit around the culm and branch base, then filled with potting soil or other rooting medium, and watered periodically to keep moist. The container can be a funnel constructed from a waterproof material such as plastic or tarpaper, or it can be a small plastic pot that is slit to fit around the culm and branch base and then resealed. McClure (1966) reports that exploratory air-layBambusa

ering studies with

tuldoides and

cessful.

Species that generate

branch

nodes,

such

fastuosa were

not suc-

root primordia

at basal

Semiarundinaria

aerial roots or abundant

as Gigantochloa pseudoarundinacea

and

Bambusa

are

vulgaris,

the most likely candidates for success.

Leptomorph

bamboos.

Attempts to propagate leptomorph

bamboos

from

culms or culm segments have not been effective. Leptomorph bamboos are very readily propagated by division or rhizomes, however, so the absence of culms or culm segments as a method is nota great loss.

Container propagation Container propagation is not a traditional method for bamboo, but it has many ap-

plications and is becoming more widespread. Hobbyists and researchers frequently grow bamboo in containers since many different species can be accommodated

in

a relatively small space, and they can be kept separated from each other far more easily than

would

be possible by planting them

in the ground.

Because

plants

grown in containers require periodic repotting or dividing, container propagation is a natural byproduct. Although rhizome cuttings alone can be taken from plants in containers, container propagation is typically a specialized form of propagation by division of a culm or culms and their associated rhizomes.

Bamboo nurseries that ship over wide distances need a ready supply of small plants that can be easily packed and economically shipped. Container propagation lends itself to this need. By continually dividing the plants, the size is kept small and

many

new plants are generated. Container propagation should be considered

whenever the number of new propagules is more important than their size. If a large number of plants is desired, the process of dividing and re-dividing can be exaggerated.

As the process is repeated,

the plants become

increasingly

smaller, but produce more culms and rhizomes, thus affording the opportunity for further multiplication and size reduction. Leptomorph bamboos grown from

seed go through a clumping stage, generating new culms from the base of existing

139

140

Chapter

4

culms. This phase can be extended by continuously breaking apart the plant into smaller sections of culms and roots. The smaller plants are considerably more sensitive to temperature, moisture, and humidity, and they may need increased shelter, attention, and care. A controlled greenhouse environment may be necessary for the smallest divisions or most sensitive plants.

A greenhouse and artificial light

can greatly extend the growing season, producing divisions for an extended period of time. This exaggerated division process is useful for increasing the number of plants of a rare bamboo.

It is also a useful method

if a large number of plants is

needed to establish a plantation and an adequate number of larger plants is unavailable. In this scenario, a portion of the divided plants would be allowed to grow larger before planting out. Although not suited to all applications, container propagation

has several ad-

vantages over field propagation. If the container is not too large, physical labor is

far less intensive than taking field-grown culm and rhizome divisions. Container plants can be readily transported to a sheltered work area, out of bright sun, rain, or excess heat or cold. New propagules can easily be moved into a shaded area, or back into bright sun, as required by the plant. For field division and propagation, the spreading root systems are seldom kept entirely intact, and it is frequently necessary to top the culms or otherwise reduce the foliage to balance the propa-

gule and keep it alive and healthy. For container propagation, if a proper regimen is followed, virtually all the roots can be retained, and foliage reduction is seldom necessary. Plants with impacted root and rhizome systems are much more difficult to divide successfully without

damaging

the mother plant and propagules. For such

plants, the roots and rhizomes cannot be fully disentangled, and division will yield fewer viable propagules. Large container plants are physically more difficult to handle, and impacted root and rhizome systems only compound the difficulty. Making the divisions. The ease and success of container propagation is depen-

dent on the ability to proportionally divide the culms, rhizomes, and roots so that the roots are not damaged and the components are in balance. A propagule with a large culm and many leaves but few roots will develop slowly and may not sur-

vive. Propagules with a small rhizome section will have fewer reserves to withstand stress and decreased ability to issue new growth. For best success, take the plant out of the container and examine the rhizome, root, and culm arrays. Often it is necessary to remove

most of the soil from the

plant, particularly if many divisions will be made and the complete structure re-

Propagation quires careful examination. The operation should be conducted in a shaded area.

The delicate root hairs are easily subject to physical damage and desiccation.

It is

often helpful to spray the root system with water to keep it moist while exposed Select a rhizome

section with at least one culm

and a proportional comple-

ment of roots. Before making divisions, decide how many propagules will be taken

and where the divisions should be. An older pair of pruning shears or loppers that can be sacrificed to the grit of the remaining soil are good cutting tools for container propagation.

A medium-toothed

saw will also work.

Make

sure the roots

are covered with soil and that there are no pockets devoid of soil. Tap the pot on the ground

to settle the soil.

A good

container soil will settle readily

around

the

roots. A 2 in. (1.25 cm) or more layer of mulch on the top of the soil to help insulate and retain moisture is beneficial and recommended, Water thoroughly

and keep the new

though

not essential.

propagules shaded until their stability can be

determined. Misting the leaves will help them withstand transplanting stresses. In moderate weather, propagules with a good root-to-foliage balance may special

treatment.

Often,

Do not allow plants to become

however,

shading

the propagules,

root bound, as has happened

require no

then gradually

in-

here. Not only does it impede

healthy growth and subject the plants to a greater risk of cold damage in the winter and rapid desiccation in the summer,

are diminished.

but the chances of dividing and propagating the plants successfully

141

Ready to divide, this groundcover bamboo is removed from the container.

=

.

Pam

Once the bamboo

a“

‘s.

Se

ae

A

is out from the container, the soil is removed, and the rhizomes are uncoiled

to determine where divisions can be made.

Any potential propagule must have sufficient roots

and one or more rhizome sections with viable buds.

The choices are made, and the three propagules are ready to be potted into new containers.

144

Chapter 4

creasing sun exposure over a several-week period may be appropriate. Observe the propagules for signs of stress so that protective measures can be employed when

warranted.

Soils. A loose, well-aerated soil that retains moisture yet drains easily is good for field-grown bamboos, but it is particularly important for container-grown bam-

boos that will be divided and propagated. It is much easier to work with the plant when the structure is readily presented, rather than trying to pull apart the roots and rhizomes from a packed ball of mud and clay. The soil should be easy to shake from the root and rhizome system so that the roots can be untangled without damaging them, A loose, well-aerated soil also promotes rapid root and rhizome growth.

Many different mixtures are possible. Formulating

a mixture depends on the

needs of the grower, the plant, and the materials at hand.

For container-grown

bamboos, texture and moisture retention are more important considerations than

available nutrients, since nutrients can be easily supplied through fertilizer applications. A good soil mixture usually consists of several components. Sand is cheap and promotes aeration, although it is relatively finely textured

and holds no water. Sand is heavy, contributing to container stability, but a large container with a high proportion of sand will be too heavy and less manageable. Volcanic cinders, perlite, and vermiculite are lightweight, stable, inorganic components. They hold water in varying degrees, yet promote good drainage and aeration. Compost, bark, and wood

chips are organic components that retain mois-

ture, promote aeration, provide some nutrients, and gradually break down. As they decompose, bark and wood chips rob the soil of nitrogen, but since fertilizing

is part of the regimen

for container-grown

higher level of nitrogen is not a problem.

plants, augmenting with a slightly

Peat holds water very well, but repels

moisture when dry. Garden soils provide micronutrients and can be economical.

A good garden soil may be satisfactory on its own since, by definition, it already contains textural components that promote soil aeration. An ideal soil for container propagation, however, calls for an even looser, more aerated texture. Some recommended soils include a mixture of four parts compost and three parts sand for most species, three parts compost and four parts pea gravel for Fargesia and other species requiring exceptionally well-drained and well-aerated soil. Examples of other, somewhat

more elaborate mixtures are 25 percent sand, 20

percent perlite, 35 percent compost, 20 percent bark chips; or 20 percent sand, 20 percent volcanic cinders, 40 percent bark chips, 20 percent peat; and so on. A wide

Propagation

variety of mixes can be effective as long as basic principles are followed. Bamboo will survive and grow even in very poor soil. Discussions of soils are largely for the purposes of optimizing growth and propagation, rather than a matter of the propagule’s survival. Managing soil for bamboos grown in containers requires more attention than is required for bamboos grown in the ground. The coarse, organic materials that provide necessary aeration tend to break down more quickly in containers, particularly if the bamboo becomes root bound. Inorganic materials such as vermiculite offer advantages in this regard, but their light weight decreases the stability of a bamboo in a container—a potential problem with large, tall bamboos. On the other hand,

their light weight

makes

it easier to move

and

handle them.

More

sand can be added as necessary to achieve the desired balance of stability and mobility. Decomposing organic materials reduce the nitrogen in the soil. Organic fertilizers can readily be incorporated when

a bamboo

is potted, but after potting,

inorganic fertilizers are usually more appropriate and practical. Liquid fertilizers, time-release fertilizers, or even lawn fertilizer sprinkled on the surface are all viable choices. Salt toxicity is usually not a problem if reasonable limits are observed. Bamboo will usually require repotting well before the buildup of fertilizer salts is a concern. Nevertheless, if salt buildup does become a problem, the soil in the container can be flushed by flowing water through it for a period of time. Container propagation of pachymorph bamboos. As with any form of culm and rhizome division, container propagation bamboos

than

leptomorph

bamboos

is more difficult with pachymorph

since the root and

rhizome

system is typi-

cally more congested. Balanced divisions are more difficult to create without damaging the mother plant or propagules. On the other hand, container division of a pachymorph

bamboo

is much easier than field division. For field divisions, the

clump sometimes needs to be partially lifted, often with great effort, to gain access

to the prospective propagules. For bamboos grown in containers, this is accomplished by simply removing the bamboo from the container. The propagule is usually severed at the narrow neck where the rhizome leaves the base of the parent thizome.

Container propagation of leptomorph bamboos. Leptomorph bamboos propagate easily. The culms are broadly spaced along the length of a rhizome, and delicate precision is seldom necessary in making the divisions. The rhizomes of lep-

145

146

Chapter 4

tomorph

bamboos

will tend to coil around

the perimeter of the container. They

should be carefully uncoiled so that the distribution of the culms and root system can be better determined. If the plant is two or more years old, the rhizome system may be branched, not simply linear, and division will be somewhat more difficult. With more rhizome area, however, the propagules will be more capable of quickly producing new or larger material than would otherwise be the case. Toward the tip of the rhizome, the roots may not yet be well developed, and it may be necessary to select a longer section of rhizome so that an adequate proportion of roots can accompany the rhizome, culm, and foliage. Some species gen-

erate new roots less rapidly, and so new culms may not yet have an adequate root system to support the foliage. In such cases, propagation will have to be delayed, or larger divisions that include rhizome sections with a more mature root system need to be selected. If many small propagules are desired, the tip of the rhizome can be twisted so it protrudes upward out of the soil. Often, the rhizome will turn into a culm, thus creating a new potential division. If larger plants are desired, however, the rhizome should be left covered by soil.

Micropropagation Though

hardly a method for the average gardener or grower, micropropagation,

or tissue culture, has a number of significant implications for the world of bamboo. In brief, in micropropagation, cells from various parts of the plant are cultured in

a specialized medium, in vitro (literally, “in glass”). Nutrients and hormones are manipulated

so that the test tube grown

cultures differentiate into roots and

shoots, ultimately forming a complete plant that can be planted in soil. Micropropagation

of bamboo

affords the opportunity

for large-scale, year-

round production of plant material. The role and importance of micropropagation for bamboos is amplified by the absence of a dependable and ongoing source of seed for most bamboos, and by the difficulty in rapidly generating easily transportable propagules on a large scale, particularly with respect to tropical pachymorph species. In addition, through specialized techniques, tissue culture offers the prospect of creating new species and forms. In plant tissue culture methodologies, cells, tissue, and organs of plants, called explants, are grown in vitro, in or on a sterile medium. In general, for the purposes

of propagation, a viable methodology must include the ability of the explant to differentiate cell growth and form a small plant, called a plantlet, and a way of wean-

ing the plantlet from the culturing medium to continue growth in ordinary soil.

Propagation

What was once solely the domain of a few laboratories is now more commonplace. According to Stapleton and Rao (1996), more than 70 species of 20 genera

have been successfully propagated by tissue culture. Complete plantlets capable of

making the transition to soil and full maturity have been achieved in many of these

efforts, including for the tropical pachymorph bamboos Bambusa bambos, Dendrocalamus strictus, Gigantochloa apus, Guadua angustifolia, and Thyrsostachys oliveri, and

the temperate-climate leptomorph bamboo Phyllostachys heterocycla . pubescens. A variety of methodologies and approaches are possible, including micropropagation from shoot tips, from seedling tissues, and from mature explants.

Each approach has limitations as well as benefits. For culturing from seedling tissues, the most vigorous seedlings can be selected, and a full flowering cycle would likely elapse before the cultured propagules would flower, but as with seeds, seed-

ling tissues are generally available irregularly and at long intervals. When tissues are chosen from mature plants, there is the risk that the propagules will flower when the parent plant flowers. If micropropagation were continued over many years, a point would be reached

where there would be little likelihood that the

propagule could reach maturity and productivity prior to flowering. The best methodology depends on a number of factors, including the nature of the species to be propagated.

Bambusa vulgaris, for example, apparently remains indefinitely

in a vegetative state. Since there would presumably be no flowering cycle, tissue

culture from mature B. vulgaris plants would appear to run little risk of a shortened period of viability before flowering. Conversely, because populations of Dendrocalamus strictus have different flowering cycles, periods of varying lengths between flowering cycles, and seed that can remain viable for up to three years, seeds and seedling explants are generally available on an ongoing basis. Culturing from D. strictus seedling tissues may be the method of choice. Small-scale field trials suggest that micropropagated plantlets of D. strictus form clumps and produce culms more quickly than plants grown from seed.

Because many tropical bamboos are more difficult to propagate by other vegetative means, and because they tend to lend themselves more successfully to tissue culture, much of the effort with respect to micropropagation has been directed toward

tropical pachymorph

bamboos.

However,

many temperate bamboo

spe-

cies, including species of Phyllostachys, have been successfully propagated via tissue culture under laboratory conditions, though success is more tenuous. Reportedly

even a slight presence of the chemical herbicide 2,4-D, for example, prevents successful tissue differentiation. Much

of the public knowledge

of micropropagation

techniques

comes

from

147

148

Chapter4

the academic world, and these techniques are most often aimed at academic research rather than mass propagation. A commercial enterprise dedicated to mass propagation

must

also actively seek reduced

cost materials that would

propriate in a research environment. For example,

be inap-

a commercial enterprise may

use jam jars rather than the expensive glassware of research labs; refined sugar as a source of carbon rather than analytical-grade sucrose; and food-grade agar instead of the highly purified agar of the research world. The commercial enterprises dedicated to mass propagation are understandably less forthcoming with proprietary information, and some methods have been patented. Nevertheless, this once highly experimental propagation method is becoming more commonplace. Although

the seductive glitter of modern

technologies often creates a head-

long rush to dispense with all that is not “modern,” including bamboo, some developing nations are realizing that bamboo’s

traditional uses still have a role in

the day-to-day existence of their peoples and, further, are realizing that bamboo

is a significant resource with a role to play in modern culture. Sometimes this realization is late in coming, Once pachymorph

long after bamboo

resources have been decimated.

bamboo has been devastated by overharvesting or elimination

of groves by the onslaught of increasing population density and the incursion of modern culture, recovery and reforestation is slow and seldom can keep pace with

the decimating onslaught. Micropropagation offers the potential for generating large numbers of readily transportable propagules, and the hope and means for restoring the bamboo resource. At the Universidad de Caldas in Colombia, Guadua angustifolia is propagated by taking microcuttings of the first shoot of a side branch from a bamboo plant exhibiting desirable characteristics. The cuttings are sterilized and planted in a gelatin culture in sealed glass containers. They develop roots, rhizomes, and new shoots, which can then be divided and planted in a soil culture. The small plants continue to generate more shoots, which can be separated into more plants, and so on. The number of propagules increases geometrically and quickly. While not for the amateur grower or field propagator, tissue culture can play

a major role in research, in the reforestation of decimated ecologies, in establishing large commercial groves, and perhaps, in discovering and generating important new food crops.

CHARTER

Landscaping and Maintenance

LONG

ASSOCIATED

WITH

TROPICAL

CLIMATES,

even

the hardy

temperate

bamboos were once regarded as too delicate for even Great Britain’s moderate climate, let alone the European continent or North America’s heartland or northern coasts, places where bamboos are now part of the garden environment. In the lat-

ter part of the 19th century, the success of 50 species of bamboo at sites in England with some of its harshest winters was clear evidence that bamboos were suited to a much broader climate than was once thought. Bamboo

is native to every continent except Europe and Antarctica. Areas of

the southeastern and south-central United States were once covered by great acreages of Arundinaria gigantea, but this native “cane” has now been reduced to a vestigial presence. To Americans and Europeans alike, managing, nurturing, using, and enjoying bamboo

are foreign. Bamboo’s

growth

habit is quite vigorous and

differs from most plants familiar to Americans and Europeans. Vigorous and unfamiliar, itis, thus, threatening. Understanding bamboo’s growth pattern enhances the appreciation of both its

beauty and vigor. That something so beautiful and of such great utility can grow so vigorously is a remarkable gift indeed.

A newly shooting culm may complete

most of its growth in a four-week period, simultaneously branching and leafingout as it continues its dramatic ascent.

A young bamboo plant can display a star-

tlingly rapid increase in presence. Where a bamboo may have been only fence high, it suddenly shields the first story of the house next door. Or where only the

149

At Hakone Gardens, a simple fence of split bamboo

attractively borders a pathway. Phyllosta-

chys and Sasa species, and another style of bamboo

fencing, border the right of the pathway.

STRESS

ohh,

o aD = a ® &S Be) iS

#

g 4) ic a Q ic] o ve =s io) G a

.s

is

=

a 2o

c o 3 o (} 9 2 = o 2 o 2

—

Bs) = o os = =ra ReC G s a

2

4 Cc o w3 oO

x) iG}

id

In this suburban landscape in the Pacific Northwest, timber bamboos create a tall screen along the fence line. In the foreground

are tomatoes,

peppers, eggplants, and herbs.

Landscaping and Maintenance

first-story windows

were shielded, the grove suddenly obliterates the looming two-story house, and fills the sky with beautiful culms and shimmering leaves. The great beauty of arborescent timber bamboos is complemented by smallersized arborescent bamboos and by shrub and groundcover bamboos. Widely varying leaf sizes and shapes add texture, and variations in culm coloration and leaf

variegation contribute vivid color and striking patterns. As a benefit to its beauty, you

can

harvest

delicious

shoots

for the table, and

culm

wood

for construction,

fencing, or garden stakes. The leaves from the harvested culms are excellent livestock forage, as well as preferred cuisine for any meandering pandas that happen

to stop by. In a variety of ways, bamboos offer a rich and abundant landscape. Once the

methods for managing bamboo’s growth are understood and applied, trepidation regarding its insistent vigor give way to a profound appreciation of its merit.

Controlling Spread Mentioning bamboo in a gathering of any size is nearly certain to prompt hysterical cursing from someone who has experienced an attack from the demonic plant that invaded unexpectedly and ceaselessly, and could not be stopped or killed. Such fear and venom is primarily directed at bamboos with a diffuse growth habit. In the United States, this generally equates to temperate-climate leptomorph bam-

boos—“runners” in the vernacular. Except for a few, usually semitropical or tropical pachymorph

bamboos with exceptionally long rhizome necks and a diffuse

habit, a pachymorph bamboo behaves much like a “normal” plant, gradually increasing its circumference as it grows. These are “clumpers” in the vernacular. Leptomorph bamboos with a diffuse habit behave in a manner largely unfamiliar to American and European cultures. Without intervention, a newly planted

leptomorph bamboo will send up new culms in a relatively close clump for a year or two, giving the impression of a benign growth

habit. Then, suddenly one spring,

new culms will emerge (depending on the species and growing conditions) many feet away from the original plant. In subsequent years, the bamboo will make additional leaps, as the now much larger plant further extends itself in proportion to its much larger size and greater vigor. By this time, bamboo is unexpectedly coming up everywhere. The invasion is in full swing, and the battle is forever lost—or so goes the tale of woe. The spread of leptomorph bamboos can be easily controlled, but to understand the methods

of control,

it is helpful to first understand

bamboo’s growth

153:

154

Chapter

5

habits. Leptomorph work

bamboos form a network of rhizomes. If the rhizome net-

remains unsevered,

all the culms, no matter how distant, remain part of the

same plant. As we have seen, the rhizomes provide the stores of energy necessary

for the brief, intense period of culm growth, and in turn, the rhizomes need the culms and masses of foliage leaves to generate energy reserves for sustenance and storage. Without the culms, and foliage leaves to sustain them, the rhizomes’ energy reserves would become exhausted, and the rhizomes would wither and die. If the culms and foliage are removed tem will attempt

from the rhizome system, the rhizome sys-

to generate new culms and foliage to nourish and sustain the

system. If the new shoots are removed before they become leaf-bearing culms capable of generating food for the rhizome system, the rhizome system will not be able to sustain itself. No new culms can emerge from a dead rhizome system. As we shall see, understanding this growth habit is key to managing bamboo’s growth and spread.

New rhizomes are relatively tender and can easily be severed with a spade. And, lacking an extensive root system, the severed new rhizomes can easily be pulled from the ground. A few species, such as some of the larger Pleioblastus, have deeper running rhizomes, but the largest running bamboos, species of Phyllostachys, have relatively shallow rhizome systems. In general, the active part of the rhizome system is shallow, not deep. An older grove may have a thick layer of rhizomes, but the lower layers will consist primarily of older rhizomes that are no

longer capable of producing new culms or new rhizomes. Unless turned downward by an obstacle, the new rhizomes of most species grow within the first foot (30 cm) or so of soil, and typically within the first 4 to 6 in. (10 to 15 cm) of soil.

Like bamboo’s aboveground culms, and unlike trees and tree roots, rhizomes do not increase in diameter with the passing years. Bamboo rhizomes are fixed in di-

ameter and shallow running. Unlike tree roots, the shallow-running rhizomes do not invade sewer pipes, nor do they enter cracks in foundations,

expanding the

cracks and weakening the structure. In this regard, bamboo is far more benign. The condition and cultivation of the soil at planting is a factor in the ability to control bamboo’s spread in future years. Bamboo

thrives in loose, loamy,

well-

drained soil. The top foot (30 cm) of soil should be thoroughly worked to encourage growth, but leaving the soil beneath unworked encourages the rhizomes to remain in the looser soil nearer the surface.

A hard-packed,

dense layer of soil

beneath a shallow layer of loose, loamy soil will make some of the various control methods easier and more effective, particularly for those bamboos that have rhizomes with deeper running tendencies. Control will be more difficult in excep-

Landscaping and Maintenan¢

tionally deep, loose, and rich soils if an abundance of water is available to the plant. Soils that are warm at greater depths can also encourage rhizomes to grow

more deeply, thus making control more difficult. The particular species’ growth

habit and

rhizome

tendencies will influence

the effectiveness of any control method and should be taken into account. The large, temperate-climate species of genus Phyllostachys are among the easiest leptomorph bamboos to control due to their relatively shallow rhizomes, whereas bamboos

with deeper, rapidly growing, brittle rhizomes, such as some species of

Pleioblastus, Pseudosasa, and Sasa, among others, are more difficult to control. For these bamboos, it is best to make additional allowances when employing any of the control methods.

Significant differences also exist among

species within the

same genus. Semiarundinaria fastuosa, for example, spreads relatively moderately, whereas

S. okuboi is rampant

and

more

problematic,

regardless of the control

method employed.

Control methods Interest in controlling the spread of bamboo has long been with us. An old Japanese practice called for digging a trench around the bamboo and filling it with seaweed, or buckwheat

husks, or the seeds of Saikachi

(Gleditsia japonica). Because

the growth habits of bamboo differ from other plants in Western culture, its control is often poorly understood. Once understood, however, controlling bamboo’s spread and maintaining

boundaries

is relatively simple.

A number

of strategies

can be employed. Each has its advantages and areas of application. Rhizome barriers. Although it requires the most initial effort, a rhizome barrier offers a nearly maintenance-free method of control. Where a grove borders an inaccessible area, such as a neighbor’s fenced yard, a rhizome barrier is the best method of control. A barrier system is reliable and trouble-free for most bamboos in most climates. However, bamboos with deep-running rhizome systems, in soils

that are loosely textured, warm, and moist to a depth of several feet (1 m or so) during the rhizome growth period, could present containment concerns. Consult local bamboo growers with similar bamboos and growing conditions to more specifically assess control concerns and barrier requirements. In this containment system, a barrier 2/2 to 3 ft. (0.8 to 1 m) deep is inserted into the ground around the desired perimeter of the bamboo grove. Approximately 2 in. (5 cm) are left to protrude above ground to allow for a build-up of mulch from leaf fall or added materials and still provide a lip above the soil. Once

155

156

Chapter

5

a year, in late fall or early spring, the barrier should be examined to ensure no rhizome has escaped over the top. In the rare event a rhizome leaps the barrier, it can be cut and pulled from the soil or simply repositioned inside the barrier. Ide-

ally, the barrier should tilt outward slightly at the top so that any rhizomes colliding with the barrier will be directed upward. If a large, vigorous rhizome is redirected downward, it could make its way underneath a marginally deep barrier. A 2' ft. (0.8 m) barrier is generally safe, but for deep, loose, sandy soils in combination with bamboos having deep and fast-running rhizome systems, one may be better off with a barrier that is 3 ft. (1 m) deep, and even at that, the plants could

still cause problems. Barriers may be made of a variety of materials. Concrete or corrugated metal are traditional barrier materials. Concrete may work well in some situations, but

itis heavy, bulky, and difficult to move or remove. Corrugated metal is less attractive, eventually deteriorates, and is not recommended

for areas with cold winter

climates because the metal conducts heat away from the soil, and so can contribute to plant losses from freezing. Fiberglass is not recommended because it is prone to cracking and breakage. Increasingly, heavy plastic is the material of choice. High-density polyethylene

(HDPE)

black plastic barrier material is available

from various bamboo nurseries and hardware stores, and can be cut to the length desired. It should be 60 mil thick and, typically, 2

ft. (0.8 m) wide. Itis light, fairly

attractive, relatively easy to handle, and is not subject to cracking, corrosion, or decay. Thinner barrier material is sometimes sufficient, but may not be reliable over

time, particularly with larger bamboos. My first barrier installations were not ideal. 1 used plastic barrier material only 30 mil thick. I did not tilt the barrier outward slightly at the top. Linstalled the barrier with a tight turn, and a portion of the barrier was directly against a jagged concrete fence post. After 10 years, the mass of

roots and rhizomes from a very large Phyllostachys bamboo forced the barrier into the jagged concrete, splitting the barrier.

A sharp rhizome also penetrated the

stressed barrier walls at the tight turn. Careful choice of materials and care in installation are key to long-term success, particularly with a large timber bamboo. When

positioning the plastic barrier, the seam should be without gaps and

should overlap by a foot or two. Ideally, the seam should be sealed with glue and rivets or small bolts, or some similar sealing and clamping method. As an extra safety precaution, the seam should be situated where any compromise of the seal, and escape of a rhizome, would be readily apparent and manageable. For example, the seam should not be placed on the outer side of the clump or grove, adjacent to the fenced border of a neighbor's property, but on the inner side of the clump or grove, away from the fence.

Phyllostachys bambusoides along a fence line, contained by a black plastic barrier. Approximately 2 in. (5 cm) of the barrier projects above the ground, but the barrier is relatively unobtrusive. As shown in the foreground, the barrier can be hidden with loose, dry leaves, but this is not generally recommended, as an escaping rhizome will be hidden from view, and moist mulch quickly becomes soil, negating the barrier. In any case, the perimeter of the barrier should be inspected in late fall or early spring to ensure no rhizomes have escaped

UI

hapter

5

Raised

beds. A raised bed is really just an aboveground

rhizome barrier. A

raised bed 2/4 to 3 ft. (0.8 to 1 m) high will keep bamboo from spreading, just as it would if the barrier were in the ground. Any rhizomes escaping over the top of a raised bed are even more readily apparent and are less likely to penetrate the soil on the other side of the barrier. Unlike the earth itself that provides supporting structure for a buried barrier, a raised bed that is sufficiently enduring to last many seasons is generally much more complex and expensive to design and build. Incorporated into architectural and landscape design, however, raised beds can offer

striking and unique displays of bamboo. A raised bed of earth with no barrier is another variation on the theme, supplemental control methods,

but

such as natural barriers, shoot removal, rhizome

pruning, and so forth, are usually necessary for complete control. Rhizome pruning. Rhizome pruning is a relatively easy, seasonal task. It is best used where the clump or grove can be readily accessed on all sides. New rhizomes grow near the surface of the soil and are easily severed. In late fall through early spring, after the rhizomes have completed their yearly period of growth, the rhizomes are pruned by plunging a sharp, flat-bottomed garden spade into the soil around the desired perimeter of the grove. Any of the severed rhizomes that have

grown outside the desired perimeter can be easily pulled from the ground. Another variation of this method calls for digging a narrow trench about | ft. (30 cm) deep around the desired perimeter of the grove and filling it with a loose

material such as sawdust, cedar bark, wood chips, or other similar materials. Instead of plunging a spade into the soil around the perimeter, a pick or similar tool

is dragged through the trench. When rhizomes are encountered, they are severed with pruning shears and pulled out of the ground. These methods are ideally suited to bamboos of the genus Phyllostachys, large

bamboos with late-maturing culm and rhizome buds and shallow-running rhizomes that can be easily severed, yet are not too brittle. Bamboos from some other genera, such as the larger species of Pleioblastus, have early maturing culm and rhizome buds and brittle, deeper running rhizomes. For these bamboos, depend-

ing on growing conditions, it may be necessary to probe more deeply into the soil to sever the rhizomes. The brittle rhizomes are more prone to break, and the earlier maturing buds may mean that any rhizome pieces left behind are much more likely to shoot. If any of the severed rhizomes or rhizome pieces are overlooked and inadver-

tently left in the ground, they can still be easily pulled out as they begin to shoot; or all the shoots can be immediately and completely harvested until there are no

Landscaping and Maintenance

more new shoots; or the new culms can be cut down before they leaf out. Since the severed

rhizomes are no longer connected

to the mother

plant, they must

shoot and produce foliage leaves to sustain themselves. If this is prevented, the weakened, severed rhizomes will perish. Many garden tillers can readily contend with new, young rhizomes, though a

mature rhizome network would stop them. In yet another variation on the rhizome-pruning theme, the perimeter of the grove can be tilled each year,

a method

that is also conducive to vegetable plots and other annual gardens as one of the sides or perimeter of a grove. Rhizome pruning is not much more difficult than the task of raking the leaves of deciduous trees in the fall. Nor is it that much

more difficult than edging the

lawn—another, more familiar grass that requires periodic maintenance to control its spread. Although the task is relatively easy, rhizome pruning is a seasonal task that must

be completed

each year, without

fail, in order to be effective.

The severed rhizomes are easiest to remove in late fall, before any significant root system is formed, but if new plants will be propagated from the severed rhizomes, late winter or early spring pruning and removal are best. Rhizomes propagated at this time will have a much better chance of survival than those propa-

gated in the fall, and they are still quite easy to remove. Bamboo growers may wish to dig up the severed rhizomes only every other year. The rhizomes and new culms will have generated root systems. They will be

somewhat more difficult to remove, but with the benefit of more vigorous and viable material that is ready to pot and sell. Containers. As we will discuss in more detail later in the chapter, bamboo makes an excellent plant for containers. When grown in this way, the container it-

self becomes the barrier for controlling spread. The drainage holes, however, are a potential source of escape for the rhizomes. A “saucer” underneath the container, similar to the arrangement for indoor plants, will prevent the rhizomes from escaping into the soil. Alternately, the drainage holes can be covered with a sturdy plastic mesh or something similar. Even

if measures

are taken

to prevent

the escape of rhizomes

into the soil

outside the container, periodic inspection is still a good idea. In most instances, it is easiest and most convenient

to dispense with supplemental

control methods

for the drainage holes, and simply check the drainage holes in late fall, winter, or early spring. If any rhizomes have escaped, they can either be cut off or repositioned inside the container.

ke)

160

Chapter

5

Natural and landscaped barriers. Natural and landscaped barriers have many

forms. Usually they work best where precise control is not critical. They may also be employed in conjunction with other control methods. Hard-packed,

unmulched

growth, and so bamboo

soil is not conducive to either rhizome or culm

will not grow in well-used paths and roads. Any new

shoots, if not harvested, will be quickly obliterated by foot or wheel. On the other hand, a dirt road that is not hard packed and dust dry during the season of rhizome

growth may allow rhizomes to pass under to a more amenable location for shoot and culm growth.

Unless there are existing cracks or fissures, bamboo

cannot shoot through

solid asphalt roads or solid concrete patios. Shallow asphalt,

however,

is some-

what friable and subject to incursion, particularly along the perimeter. An asphalt

road will easily stop a small suburban plot from spreading, but if the layer of asphalt is shallow, a large grove of timber bamboo could send the rhizomes underneath the road to the other side. A sidewalk may control groundcover bamboos, but not larger bamboos, which can readily send rhizomes to the other side of the sidewalk. Similarly, a wide but shallow concrete patio may not stop a larger grove of bamboo,

but it could be an effective barrier for a smaller bamboo grove.

If adequately deep, any manner of unbroken

vertical barrier, including rock

faces, walls, or building foundations, can stop bamboo

from spreading. The hard,

pointed rhizome tips may find their way into small openings, but unlike tree roots, bamboo

rhizomes

remain

a fixed diameter and do not expand and break apart

what they have penetrated. Water also stops bamboos from spreading. Streams, ponds, lakes, and irrigation ditches are natural barriers. Because livestock eat new shoots and leaves, a fence with livestock on the other side is also an effective barrier.

Shoot removal. A thick grove of bamboo is very difficult to remove, but removing new shoots before they develop into culms is easy. Most bamboos shoot in spring and early summer. If a new shoot emerges where a culm is not wanted, simply remove the tender shoot by twisting or breaking it off at or slightly below soil level. Shoot removal is a good method where precise control is not critical. It would not be a good method along a fence line with a neighbor—unless the neighbor is readily willing to participate in the shoot harvest. Shoot removal limits, but does

not stop, the spread of rhizomes. The rhizomes of a small clump of bamboo may spread less than 6 ft. (2 m) or so away from the aboveground clump, but the rhi-

Landscaping and Maintenance

zomes of a very large bamboo in amenable soil may eventually generate shoots 50 ft. (15 m) or more from the nearest culm. Even on a smaller scale, in many urban and suburban situations, the incursion of rhizomes into other garden areas may be

problematic, and shoot removal may be insufficient for the desired result. In other situations, where some freedom is permitted, shoot removal is an excellent control

method

involving relatively little effort. The expanded

rhizome

and root area provides more energy for the grove, and the harvest of shoots is a welcome boon for the table. If the roaming area for rhizomes happens to be a lawn, lawn mowing is an effective variant of the shoot removal method, though it does not offer a harvest of shoots as a benefit, and bamboo

roots will compete

fiercely for soil moisture.

Eradication Bamboo nurseries sometimes offer bamboo removal services. Depending on the type of bamboo, the nursery, and the local market, you may be paid for the bamboo, charged for removal, or the removal may be free. Some nurseries have spe-

cialized tools that enable them to cut through a well-established grove’s thick cake of rhizomes. These chunks of the grove can then be potted and sold to their customers. Killing bamboo is not easy, but it can be done. It is essential to remember that a grove is not a group of bamboo plants (unless more than one plant was originally planted to establish the grove), but must be treated as a single plant connected by a network of rhizomes. If only a portion of the grove is to be killed, then that por-

tion must first be separated from the rest of the grove. Such a situation is common when bamboo crosses over from a neighbor’s property. Severing all rhizome con-

nections between the property lines is essential. Attempts to kill bamboo on one side of the property line will be unsuccessful as long as the rhizomes remain connected to the bamboo on the other side of the property line. Unfortunately, unlike the yearly regimen of pruning the tender new rhizomes around the circumference of a grove, cutting through the thick, dense cake of tough, woody rhizomes at the core of an established grove may be very difficult without a specialized tool or reciprocating saw. Lacking such tools, an ax as well as a sharp spade may be necessary. Several suppliers and bamboo

nurseries

sell specialized

tools for cutting through the cake of old rhizomes. The tool consists of a heavy metal rod with a sharp, heavy cutting blade welded to the bottom of the rod. A long, heavy, metal

sleeve fits over the rod. The sleeve is lifted, and dropped or thrust downward,

lol

162

Chapter

5

pounding the cutting edge through the cake of rhizomes. The principle is similar in concept to a metal fence post and the sleeve for pounding it into the ground. Reciprocating power saws and power digging tools are other options, though considerably more costly and noisy. Bamboo

all culms and breaking off

can be also eliminated by cutting away

any new shoots before they leaf out. Because a bamboo plant must have leaves to nourish itself and store energy in the rhizomes, depriving it of this source of food will exhaust the rhizome’s energy reserves, causing it to wither and die. Systemic herbicides alone can often eradicate bamboo, but bamboo is very resistant, and several herbicide applications may be necessary. If herbicide drift is a concern, the tall existing culms can first be cut down or pruned to a height that makes herbicide drift manageable. Although repeated herbicide application may eventually eradicate bamboo, most environmentally tolerable herbicides need a plant to be in foliage for the herbicide to be effective.

Bamboo

uses the foliage

leaves not only to sustain itself, but also to generate energy reserves for its rhizome

system. If herbicides are used, they are often best employed in a regimen that, at some point in the process, discontinues herbicide application and calls for removal of new shoots before they leaf out. Bamboo can be eradicated without the addition of any herbicides or chemical

fertilizers, but these can be employed to accelerate the process. There are variations on the theme, but an effective regimen for eradication is as follows: cut the

aboveground growth to the ground with a lawnmower, pruning shears, hand saw, chain saw, or other implement, as fits the situation. Water and fertilize to encourage the rhizomes to generate new growth. If necessary, limit the height of the new

shoots by pruning. As soon as the new shoots have leafed out, stop all watering, fertilize very heavily with a high-nitrogen

fertilizer, and spray with a strong her-

bicide. Remove the culms and foliage once the herbicide has been fully absorbed. Remove all subsequent shoots before they leaf out. Damaged by the herbicide and stressed and weakened by overfertilization and lack of water, the bamboo’s demise

is accelerated. On a

larger scale, bamboo can also be removed

by cutting down the culms,

then ripping up and removing the rhizomes with a tractor or similar machinery.

Controlling Height In landscaping and garden situations, it is often desirable to have bamboo

within a specific height range. For example,

grow

a bamboo screen may need to grow

Landscaping and Maintenance

sufficiently tall to block the view from a neighbor’s window, but not so tall as to block the sun. Various strategies can be employed to control height. Selecting bamboo according to its height potential is the most fundamental of these strategies.

Choosing bamboo for height In selecting bamboo for specific height ranges, one must consider growing conditions, size of the grove, and acceptable time for reaching the desired height. The

heights listed in this book represent the maximum height possible for a large, mature grove, under ideal conditions. In most instances, a small grove in a typical landscaping situation will never attain the listed maximum

height. It is also well

to keep in mind that up to a decade or so is required for a grove to fully mature and for the culms to reach their maximum size. The most rapid gains occur well before the grove matures, and yearly increases diminish as maturity approaches. If a landscaping need calls for a screen at a height in the range of 15 to 20 ft. (5 to 6 m), for example, Pseudosasa japonica,

a bamboo with a maximum height of

about 18 ft. (5.5 m), would seldom be a good choice. In a small plot, even under ideal growing conditions, the plant would require many years to approximate the

desired height range, and even the minimum of the range might never be reached. A much better choice might be Phyllostachys bissetii, P. aureosulcata, or even P. nigra var. henonis, if growing conditions are particularly difficult. Although these species

are capable of growing much taller than that desired for the screen —as much as 65 ft. (20 m) in the case of P. nigra var. henonis—it is much easier to limit the height of a taller bamboo than it is to stretch the growth potential of a smaller one.

Where

harsh winters are common,

ground, a bamboo’s maximum

and culms are frequently killed to the

attainable height is significantly reduced. Here,

the relative hardiness of a species plays a significant role.

A hardy bamboo such as

Phyllostachys nuda, which has a maximum height of about 34 ft. (10 m) under ideal conditions, may actually grow taller than P. bambusoides, one of the largest, temperate-climate, timber bamboos, with

a maximum

height of more than 70 ft. (21

m). When grown in cool temperate climates, semitropical pachymorph bamboos, such as some members of the Bambusa genus, may escape winter damage but still not achieve anywhere near their maximum growth potential. Most bamboos of the sun-loving genus P/ryllostachy s will not grow as tall or spread as fast if they are planted in shadier growing conditions, although P. nigra

prefers less sun and moister, more temperate conditions than most other members of the genus. It grows much larger in northern California and the Pacific Northwest than in southern California or New England.

163

164

Chapter 5

Other bamboos seldom achieve anything approximating maximum height, even if the basic climatic factors seem favorable. Among the most notable and notorious is Phyllostachys heterocycla {. pubescens, the world’s largest temperate-climate bamboo, with a maximum height of 90 ft. (27 m). It can, though seldom does, approximate

its full growth

potential outside of Asia. Although

a beautiful and

rewarding bamboo, it is somewhat unpredictable and difficult to establish, and it would not be the first choice where a quickly established screen of a reliable height is important.

The experience of other bamboo growers in the same local conditions will provide helpful guidelines in choosing species for height. Although not necessarily in the most ideal ways, the height of a bamboo culm can, at least, always be reduced, but again, you cannot make a bamboo culm taller than it already is. In choosing bamboo for height, it is best to err on the side of too tall, rather than not tall enough.

Limiting height If landscaping range, bamboo

or other needs do not require bamboo is best left unlimited.

If necessary,

within

however,

a specific height

height can be con-

trolled by modifying growing conditions or through mechanical methods such as pruning.

Water, fertilizer, and sunlight. The general growing conditions for a given area are fixed and should already be part of the criteria when selecting a species for a particular site. Other conditions may be relatively or entirely fixed. The shade provided by a building is usually a fixed condition. Shade provided by tree branches,

however, is only a relatively fixed condition, depending on the degree one is willing to prune or let the branches grow.

The amount of water and fertilizer that the plants receive are subject to direct and ongoing modification, and these are key elements that can be manipulated to control height. Particularly in drier growing areas, bamboo

can be watered only

enough to keep the grove healthy and at the desired height. Little or no fertilizer will also limit growth, particularly in poor soils.

Pruning and other mechanical methods. Pruning is discussed in detail in the following section of this chapter, but cutting the top off a culm at the desired height

is a very direct way of limiting height. If much is removed, portions of the upper branches may need to be reduced to restore some of the culm’s graceful taper. For

Landscaping and Maintenance

a dense hedge effect, the bamboo culms and branches can be topped and pruned in much the same manner as a conventional hedge. Cutting through the rhizomes at periodic intervals within the grove effectively creates smaller plants with less extensive rhizome systems, which may also be effective in reducing the size of the culms and the vigor of the plant. Removing the culm leaves before the internodes have completed lengthening

is another method of limiting height. It also increases branch density. This process requires at least daily attention during the period of most rapid culm growth. A culm can be stopped from growing any further by removing all remaining culm leaves. These practices are more commonly applied to bonsai bamboos, but can be experimentally applied for other purposes as well.

Thinning and Pruning As with all landscape plants, thinning and pruning contribute significantly to bamboo aesthetics. Thinning and, to some extent, pruning also play a direct role in the health of a bamboo grove. Because their cultural requirements differ from those of other more familiar plants, bamboos are often improperly maintained in West-

ern landscapes and gardens. Bamboo is easily one of the most beautiful landscape plants, yet lack of understanding often conspires against it, and the clumps or groves encountered in landscapes of the Western world are often tattered, unattractive thickets.

A thoughtful thinning and pruning regimen will have a major

impact on both the aesthetics and ongoing health of your bamboo.

Thinning Thinning is essential for a healthy and attractive bamboo grove. The need for thin-

ning applies to plantings of all sizes, from a bamboo forest covering many square miles to a small container on the patio. Only groundcover bamboo is not normally thinned, but it benefits from periodic pruning for some of the same reasons.

The heavily shaded interiors of unthinned groves have areas of dead or halfdead branches and leaves. Old and unhealthy culms compete for space and light with new, potentially healthy culms, making the new culms unhealthy and tattered looking as well. Bamboo left unthinned for several years has the appearance of a congested thicket, rather than the striking beauty of a well-tended grove. A healthy grove must be thinned so that sunlight can penetrate the foliage canopy. If a grove is thickly populated and shady, shoot emergence will be delayed. In addition, densely spaced culms produce correspondingly dense rhizome

165

166

Chapter 5 growth, which

in turn produces lower

quality

shoots for harvesting, and smaller

culms. If the culms and branches are too dense, new culms will be unable to properly branch and

leaf out, and the new culms may die. Damaged

culms are the first candidates for thinning.

and

misshapen

Next are the older culms and

sized culms. Culms three to five years old have reached their maximum and are ready

strength

for harvest. Grove density and the importance of strong culm wood

versus grove appearance will dictate when production rather than culm wood

the older culms are taken. When

Less vigorous culms are harvested earlier.

is grown as a hedge, periodic

spacing can be much

shoot

is the principal interest, vigorous culms may be

left unthinned for seven or eight years. If bamboo

under-

tighter. By definition,

thinning is still warranted,

but culm

a hedge has limited depth, so light can

Looking closely at this grove of Phyllostachys, you will note the dark green chairs nestled in the grove. The owner has created a private, tranquil sanctuary by carefully thinning the grove. A narrow pathway leads to this peaceful retreat.

Landscaping and Maintenance

still penetrate relatively well even with close culm spacing. Often bamboo hedges are topped

for uniformity or to reduce the height of the hedge. If the bamboo is topped, light can penetrate even more easily than would be the case with an equally dense but taller hedge. An effective screen can provide a partial or total

visual obstruction as desired, but sufficient light must nevertheless reach the inner culms and foliage. Conveniently, bamboo lets us know when we have exceeded its density limits—large, new, vigorous, healthy culms will fail to branch, and the culms eventually wither and die. Even in a hedge, culm spacing cannot be overly

dense and must allow at least some light to reach the inner leaves some of the time.

In a grove, medium-sized and, especially, timber bamboos look best when spaced so that they appear as individual culms in the grove rather than as an in-

distinguishable part of a mass planting. This same aesthetic applies in a deciduous forest, as well as with other plants. Space makes the individual culms appear larger and gives stature to the culms as well as the grove. The contrast between massive culms and

their delicate foliage is an essence of bamboo’s beauty. The sub-

stantial stature of the culms emphasizes the delicacy of the foliage, and vice versa. Whether the “grove” is a bamboo forest or a small border plot in suburbia, similar aesthetic considerations apply.

Conveniently, in this regard, the needs of a healthy grove coincide with aesthetics. A rule of thumb for leptomorph

bamboos calls for 1 ft. (30 cm) of space be-

tween culms for every 10 ft. (3 m) of height. This ratio is merely a rough guideline, however,

and should not be adopted

as a

rigid rule. In practice, the ratio holds

better for large groves of tall bamboo, but breaks down for small plots of shorter bamboo. If bamboo is planted in a narrow strip along a border, for example, more

light will penetrate than if the grove were larger or wider. If screening is a primary consideration for the border planting, closer culm spacing might be desirable. In a new planting of bamboo,

“grove,” and maximum

where light has no trouble penetrating the modest

leaf area is desirable to fuel the engines of growth, culm

spacing may be much tighter than the 1 ft. (30 cm) to 10 ft. (3 m) rule, or the interpolated 6 in. (15 cm) to 5 ft. (15 cm) ratio. In a hot, dry climate, it may be desirable to thin less intensely, so that the foliage canopy prevents light from drying

out the soil. Conversely, in a cool, wet climate, it may be desirable to thin more, so that the sun can warm

the soil and encourage rhizome and shoot growth.

A “walk through” grove of leptomorph bamboo is one of the great aesthetics of the bamboo

world,

and conveniently again, it generally coincides with com-

mercial interests of pole and shoot production. Additional emphasis is given to

167

168

Chapter 5

thinning out the smallest culms and shoots, letting stand the largest shoots and

culms, thereby fostering the production of larger shoots and culms in subsequent seasons. In Japan, it is traditionally said that the optimal spacing in a bamboo forest would allow a person to walk within the forest with an umbrella open. Another guideline indicates that the spacing should allow herbaceous plants to survive on the forest floor, but not grow very thickly.

As the culm size of the grove increases, the spacing between the culms can be increased. Another of the many rules of thumb calls for spacing of at least 2 ft. (0.6 m) for culms 2 in. (5 cm)

in diameter,

and at least 3 ft. (1 m)

for 4 in. (10 cm)

culms. As the culms increase in size, the shoots will tend to be fewer in number and more widely spaced, but larger. Caution should be exercised not to space culms too widely. The culms support one another against wind and the weight of snow. If the culms are too widely spaced, some may bend too far in the wind and snow, causing them to break or become lodged against other culms. One strategy calls for spacing the culms more densely at the grove’s perimeter, then opening the spacing toward the interior. Species, foliage density, grove size and shape, the goals of the grower, climate, amount of available light, and other local conditions are all contributing factors in determining optimal culm spacing. Fortunately, great precision is not a require-

ment, and if it is later decided that a different thinning regimen would be better, new culms will grow within a year, and existing culms can be thinned at any time. If a grove is used solely for pulp production, it may warrant no thinning. this scenario,

fast-growing

varieties are encouraged

densely for a few years, and are then

harvested.

to grow

rapidly and

For this purpose,

In

very

the mass of

pulping material is the key element, not shoot size, culm size, or aesthetics. At the other end of the scale, if the fresh, bright appearance of new culms is paramount, culms can be thinned when they are two to three years old. This is not

generally recommended, however, as the harvested culms will be immature and weak, and the grove will never develop its full growth potential. Although thinning can be done throughout the year, it is typically carried out in the fall or winter, after the culm and rhizome growth periods have been completed, and well before the new season’s growth begins. Food reserves are stored in the culms as well as the rhizomes. Pachymorph bamboos are particularly dependent on culms for energy storage. It is best avoid thinning just before or during shooting, as the diminished energy reserves reduce the bamboo’s ability to produce new shoots and culms. Moreover, particularly in tropical environments, starches stored in the culms

in preparation

for the impending

shooting

period

Landscaping and Maintenance

make the harvested culms more vulnerable to insect attack. Sometimes, circumstances force one to thin at the least optimal time, just prior to or during shooting—and as I write this, 1 am personally seeing the result: far fewer spring shoots from those bamboos that I just recently thinned. In forests of Phyllostachys heterocycla {. pubescens in China, it is not permissible to take immature culms, harvest during the growing season, or take culms that bear winter shoots for harvest. In a mature grove of leptomorph bamboo, the number of harvested culms would not exceed the number of newly matured culms. Once a bamboo

is established, a portion of new shoots can be harvested for the table.

This can be a prospective form of thinning, taking smaller shoots, or shoots from congested areas of the grove, or where new culms are not desired, while letting the

shoots grow where new growth is wanted. Culms should never be thinned with a hatchet or an ax. This method damages

the culm that is being harvested, risks damage to nearby culms and rhizomes, and leaves jagged stubs in the grove. Leptomorph bamboo culms should be sawed, flat across, at their base. The culms of subtropical and tropical pachymorph bamboos are vulnerable

to rot or rhizome

damage

and are usually sawed

higher, always

above a node, at roughly 4 to 8 in. (10 to 20 cm) or more above ground. Large, old, pachymorph bamboo clumps eventually become impacted at their centers if an ongoing thinning regimen is not followed. One method for revitaliz-

ing such a clump calls for cutting a path or section into the center of the clump, thus forming a horseshoe pattern with the remaining culms. This provides access to the center of the clump for additional thinning and management, and it clears away old growth, making way for healthy new growth in the clump’s center. This regimen is more effective if it is carried out before the clump becomes too large and

too severely impacted. Pruning Thinning, in the context of this chapter, is the removal of entire culms. Pruning is the removal of branches or parts of branches and culms. Unlike thinning, pruning is not usually necessary for the health and vigor of a grove. Top pruning, however, is sometimes warranted to prevent wind or snow from breaking new culms. Pruning is not always necessary for aesthetics, but it can significantly enhance the appearance and usefulness of bamboo.

Sometimes limiting the height of a screen is desirable. A strip of bamboo may be planted to shield a sidewalk, roadway, or neighbor’s window, but limiting height may be beneficial to allow a distance view or to prevent excess shading.

169

170

Chapter

5

Planting bamboo but

goal,

a new

height—and

then

that grows only planting one

to the desired height many

require

may

is betting that

achieved in one’s local conditions.

the

seasons

theoretical

is one way to attain maximum

its maximum height

can

be

Another method calls for planting bamboo that

is readily capable of achieving more than the desired maximum iting water and fertilizer when

to achieve the

height, then lim-

the desired height is achieved. Simply topping the

bambooat the desired height is another, more precise, though less natural, option. Depending on the degree of topping, the upper branches may need pruning so the plant will have a more natural taper. The culms should be topped just above a node.

This from tains view

bamboo hedge consists of several Phyllostachys species. The roof of the home is visible the roadway, but the living room windows are shielded from view. The homeowner mainthe hedge at a height that screens the view from the street, but still permits a distance and allows ample sunlight to enter the garden. On the left and right areas of the hedge,

the season's unbranched

new culms project far above the pruned height of the screen.

The new

culms will be topped and the branches pruned to integrate the new growth with the old and

maintain the same relative height of the hedge.

From the interior, looking toward the roadway, this photo was taken one year later than the preceding one. The new growth from the previous year has been integrated into the hedge The hedge was thinned in the fall to make way for the new growth. This year’s new spring growth, illuminated by the setting sun, has begun to branch. As with the previous year’s new growth, the culms will be topped and the branches pruned to integrate the new growth with the old and maintain the hedge’s height

192

Chapter

5

Ifa more s vere hedge effect is desired and culm spacing is sufficiently dense,

the side branches can be pruned

the same

in much

manner

as a conventional

hedge. If the side branches are left unpruned, or only slightly pruned, the hedge will have a more informal, natural appearance. For the same screening effect, however, this type of hedge requires more lateral space than a bamboo hedge that is pruned more severely. Depending on the landscaping need, one hedge-pruning regimen may be preferable to the other. Both are attractive. Pruning allows bamboo to be used in many more ways in the garden and landscape, and it allows specific bamboo to be used in ways that would otherwise be unsuitable. For example, some bamboos,

like Phyllostachys bambusoides, have a

strongly upright habit, but others, like P. nigra, have an arching habit. With its black culms and branches, gracefully arching stature, and delicate foliage, P. nigra is among the most beautiful and graceful bamboos. Its arching habit, however, can be a problem in some settings if the arching culms block pathways or shade other plants. The culms arch more as the foliage fills out. Rain or snow will make the culms arch considerably

more. Topping

the culms

and

pruning

the upper

branches reduces the arching tendency and may permit P. nigra to be planted where it might otherwise not be suitable. And although some might regard pruning P. nigra into a hedge as heresy, the black culms and branches and the delicate foliage make a strikingly beautiful hedge.

As suggested in the section on thinning, the contrast between sturdy culms and delicate foliage is an important aspect of bamboo’s appeal and beauty. Just as a tree has more stature when its trunk is not covered to ground level by branches and foliage, so too, medium-sized and timber bamboos have more stature when the bases of their culms are not covered by foliage, but are exposed so that the masses of delicate foliage contrast and emphasize the stature and strength of the

supporting culms. In some species, the lower branch

nodes remain dormant.

Other species immediately branch at the lower nodes. Removing the lowermost branches to expose the lower part of the culms can enhance the beauty of a grove.

Ina larger, more mature grove, the lower nodes are more likely to remain bare. An immature grove, or a smaller grove or plot typical of landscape situations, is more likely to have branches on the lowermost nodes that can be removed to enhance

aesthetics. A variety of special effects are possible with pruning. Each season, branches

ramify,

producing

more

branches

and

more

foliage.

existing

Shortening

the

branches the first year, and continuing to prune back the longer new branches,

produces very dense foliage close to the culm. Most shoots can be removed so that

Landscaping and Maintenance

the specially pruned bamboo can stand apart as a specimen plant. One culm, a small group, or many culms can be pruned in this way. In another, more unusual technique, culms are encouraged to grow very close together in a tight clump and the lower branches are removed. The dense clump of culms has the composite ef-

fect of a “trunk” supporting the foliage. A well-developed root and rhizome system is required to support tall growth of this density. The root and rhizome system is encouraged to grow outside of the tight clump, but shoots emerging outside of the clump’s perimeter are removed.

These examples

illustrate two of the many

special effects that are possible with pruning. Culms and branches should be pruned just above a node. Smaller branches, and bamboo

that is pruned into a hedge, can be pruned more casually along the

internode, though pruning

just above the node is always preferable. A long, open section of internode is aesthetically undesirable, and it can trap water or harbor undesirable

organisms.

If a culm

is topped,

it should

be topped just above

the

node, and the upper branches should be pruned to restore the natural taper of the foliage canopy. First-year culms and branches are easily pruned with pruning shears or loppers. If the culm is an inch (2.5 cm) or more in diameter, sawing with a fine- to medium-toothed saw is preferable. As the culms get older and harder, a saw becomes the tool of choice. When entire branches are removed at the culm node, different methods may apply, depending on the species. Pseudosasa japonica branches,

for example, can usually be removed by snapping them downward. The branches of most bamboos can usually be removed satisfactorily with pruning shears or loppers. Sawing the branches

instead of severing them

with pruners or loppers

typically yields a cut more flush with the node. To cleanly remove a branch from Phyllostachys bamboo, through

saw the underside of the branch

at its base, where it joins with the culm,

about a third of the way

then snap the branch

down-

ward. The branch should break away cleanly and evenly at the node. Small bamboos benefit from periodic trimming to renew their bright fresh ap-

pearance. Most variegated forms lose some of their bright variegation by the end of summer. Cold winters also take their toll, browning parts of the leaves and giv-

ing the plant a tattered look. Trimming the outer foliage renews its appealing freshness. New branches and leaves will grow to cover the exterior of the plant. Early spring is the best time to trim the plants, just before the new shoots, branches, and leaves emerge. Hedge trimming shears work well for most dwarf bamboos. A large area of dwarf groundcover bamboo can be cut with a lawnmower.

Every

few years, in late winter or early spring, groundcover bamboo can be more thor-

bye

oughly

freshened

and

revitalized

by completely

cutting

it to the ground.

The

spring’s new shoots and leaves will completely restore the groundcover. This procedure should not be applied, however,

unless the groundcover bamboo is well

established and healthy.

iN

NLS

a

1

i

Ty.

li

The Pleioblastus fortunei in the foreground suffered heavy winter damage. In the background, Sasaella masamuneana ‘Albostriata’ is not heavily winter damaged, but the variegation has diminished. Both can benefit from heavy pruning.

J

The Sasaella and Pleioblastus plants from the previous photo, as well as Pleioblastus pygmaeus var. distichus (bottom), have been heavily pruned in early spring

After the heavy pruning in early spring, the lush, fresh foliage is restored by early summer.

Landscaping and Maintenance

Container Bamboos Bamboos make excellent container plants, although their vigor often demands relatively frequent repotting. Because most bamboo culms and branches are hollow, a container of bamboo weighs much less than a container of most other plants of similar size. A large potted bamboo

remains relatively mobile, limited more by

the weight of the soil than the weight of the bamboo itself. In urban

and suburban

settings, a strategically placed container along the

perimeter can immediately create a much needed privacy screen. Container bamboo can also play a transitional role in the landscape or garden, providing a temporary screen until

a more permanent screen, such as a tree or shrub or a new

desirable bamboo, grows to size, or as a supplemental screen in the winter months when

deciduous trees lose their leaves and screening ability. In the summer

months, the same bamboos can be moved to a deck or porch to provide a secluded and welcoming environment

for summer’s outdoor activities. The scenarios and

possibilities are open-ended. Container bamboos are also a boon to hobbyists and researchers, as many different bamboo varieties can be grown and observed without a major commitment of space and other resources. Small plants that exhibit desirable characteristics can be moved to larger pots or planted in the ground. Bamboo nurseries, particularly those that specialize in shipping small plants, find container growing and propagating ideally suited to their needs. Growing leptomorph bamboos, and pachymorph

bamboos

with a diffuse

habit, in containers automatically controls their spread. If containers of these bam-

boos are placed on the ground, they should be examined at least once a year, and any rhizomes that poke through the drainage holes should be cut off or repositioned back into the container. Although pachymorph bamboos with a caespitose habit do not need the benefit of a rhizome barrier to limit their spread, they also grow well in containers. Many of these bamboos are not hardy. Container growing allows the plants to be

moved to more protected areas, as necessary, according to climate and season—or they can be grown indoors.

Container-grown bamboos are more subject to various stresses. Soil dries out

more quickly, particularly if the rhizome and roots fill the container solidly. If winter temperatures drop to freezing and below, an unprotected container will freeze much more quickly than the ground. Even if the cold would not otherwise harm a plant, if the root system remains frozen for an extended time, unreplenished

Ly

178

Chapter

5

moisture loss from the leaves may eventually kill it. Drying winds and sun exacerbate the problem. Smaller containers are more prone to freezing than larger containers. In marginal climates, wood chips, sawdust, leaves, or other forms of mulch can be mounded

up around the containers. Where practical, containers can be

clustered together, with the less hardy plants in the center, then mounded

with

mulch. The larger mass of the cluster better resists freezing, and the dense foliage of the clustered plants also helps insulate the plants and containers. In more severe

climates, where winter damage and survival is a concern even for field-grown bamboos, ground,

container bamboos or moved

may

need to be buried, container deep,

to a sheltered greenhouse

in the

area.

A soil mixture for containers must drain quickly yet retain moisture—seemingly conflicting requirements. In general, coarser material promotes drainage and aeration, but moisture requirements can be met if at least some of the coarsely textured material is capable of retaining moisture. Moisture retention is more of an

issue with container-grown plants, and all the more so for plants with an extensive leaf canopy and extensive root and rhizome systems. A top layer of mulch

helps retain moisture. Fertilizer requirements for container bamboos grown bamboos

are similar to that for field-

(discussed in the “Cultural Requirements” section of chapter 3),

but a few other considerations apply. Some soil mixes, particularly those specifically chosen for seed propagation, may contain little or no organic matter. For those soil types, a weak application of fertilizer should be given at each watering. The soil mixtures with little or no organic materials, clay, or loam will benefit from

fertilizers containing micronutrients, particularly if the plants are expected to remain in container for any length of time. Mixtures with wood chips need a fertilizer with slightly higher nitrogen to compensate for the nitrogen loss as the wood

chips decompose. Ifa bamboo remains in container and is fertilized regularly, harmful salts may

gradually build up. Indoor plants are more susceptible to salt buildup, and they benefit from

leaching every few years. Taking the container outdoors and run-

ning water through it flushes the salts from the soil. This treatment can be applied to plants grown outdoors in containers as well. Climates with seasonally heavy rainfalls will automatically accomplish the task without additional help from the grower.

Most plants grown in containers eventually become root bound and require repotting, dividing, or root pruning to revitalize them and make room for healthy growth. Bamboos are no different, except that they are very vigorous and become

Landscaping and Maintenance

root bound more quickly than many other plants. Because several factors are in-

volved, declaring a simple rule of thumb on repotting is problematic. In general,

plants in containers should be checked every two years to see if repotting, dividing, or root pruning is needed. Large, vigorous bamboos may require examination

every year. A root-bound

plant is far more

susceptible to winter freezing and summer

desiccation. A soilless, root-filled container saps vigor, inhibits healthy growth, and diminishes the likelihood that healthy vigorous propagules can be made by dividing the plant. I have thoroughly watered a root-bound bamboo only to find that the center of the soil and

root mass remained completely dry. Root-bound

bamboos may shoot weakly, if at all, and new rhizome growth may be limited or nearly absent. Bamboos are excellent container plants, but one must remember to repot, divide, or root prune them with some frequency.

Sizes, Shapes, and Colors Bamboos in cultivation range in height from a few inches to 100 ft. (30 m). Diameters range from less than one-sixteenth of an inch (about 2 mm)

to a full foot

(30 cm). Leaves range from delicate and tiny to leathery and 2 ft. (0.6 m) long and 4 in. (10 cm) wide, with colorations that include deep green, lime green, yellow,

white, and a variety of striping combinations. Culms come in varying shades of green, black, yellow, brick red, and green-blue, and they can be variously spotted and striped. Landscaping considerations call for choosing bamboo

first according to size

requirements, then selecting suitable shapes, textures, and colors. As with any landscaping plant, contrasting sizes, textures, and colors help individual differ-

ences stand out and more readily engage the eye and spirit. A towering timber bamboo, for example, is nicely set off by an understory of variegated dwarf bamboo. The timber bamboo

can also help create the partially shaded

environment

that many of the dwarfs need. Both of these may be enhanced by a nearby largeleaved bamboo

“bush.” Bamboos

with yellow culms and bamboos with black

culms are all the more striking when planted next to each other. The possibilities are endless. Like most things, especially living things, bamboo does not lend itself to simple categorization. Pleioblastus chino var. vaginatus {. variegatus is commonly grown as a groundcover,

but it can reach a height of 10 ft. (3 m). Hibanobambusa tran-

quillans ‘Shiroshima’ is sometimes grown as a bush, but it can reach a height of 16

theses

Clumps of Bambusa

textilis are an attractive backdrop for the pond at Quail Botanical Gardens.

Landscaping and Maintenance

ft. (5 m). Bamboos of the genus Phyllostachys have a treelike shape and can reach a height of 90 ft. (27 m), but they can also be pruned and trained to form a hedge.

Most bamboos only reach their maximum size under ideal conditions in large,

free-running groves that are 10 or more years old. For typical landscaping situations, anticipate a size of less than the listed maximum. As discussed elsewhere in

this book, it is easier and better to limit the size of a bamboo than it is to wait for the bamboo to attain a size that it may never achieve.

Dwarf bamboos Dwarf bamboos include species that typically reach a maximum height of less than 6 ft. (1.8 m), though most in this category have a maximum height of no more than 4

ft. (1.2 m). In a typical landscape or garden setting, they are usually less

than 2 ft. (0.6 m) tall, employed as bamboo lawns, groundcovers, or low-growing

understory plants. Dwarf bamboos are almost exclusively associated with small, woody, leptomorph bamboos. Most dwarf bamboos are bushy plants with lepto-

morph rhizomes, having culms no more than a 4 in. (6 mm) in diameter, Many herbaceous species of bamboo also fit the dwarf category. They can be quite attractive, but the tropical requirements of most herbaceous bamboos limit their usefulness in North America. Typically, the culms of dwarf bamboos are nearly obscured by the foliage. Many

of the dwarfs,

particularly

those of the genus

Pleioblastus, are excellent

groundcovers. In areas at risk from soil erosion, a groundcover of dwarf bamboo is highly effective at knitting the soil together and preventing erosion. Dwarf bamboos also make attractive container plants for an outdoor deck or the confines of a condominium balcony. Height is controlled and leaves are freshened by trimming or mowing in early spring. Many species of the genus Pleioblastus, as well as other genera in the dwarf category such as Sasaella and Shibataea, can grow taller to form a bush or low hedge. The dwarf bamboos

include many

with variegated leaves. Leaf size, striping

patterns, and coloration vary considerably,

offering a wide choice for the land-

scape. Variegation is usually strongest in the spring, fading as the season progresses. Some species hold their variegation better than others. Pleioblastus fortunei, for example,

retains

its variegation

exceptionally

well,

whereas

P. viridistriatus,

though striking in the spring, fades more quickly as the season progresses, partic-

ularly if exposed to direct sun. Some varieties react to other conditions. In Sasaella masamuneana ‘Albostriata’, for example, the first leaves to appear are the most re-

liably and strikingly variegated, the later leaves less so.

181

182

Chapter

5

Although the variegated forms are among the most appealing dwarf bamboos, the green-leaved

forms are varied and attractive as well. Pleioblastus pygmaeus,

often mislabeled Sasa pygmaea, is among

the most widely available dwarfs, al-

though the name has become a misused generic for any small bamboo.

Pleioblas-

tus pygmaeus var. distichus is very short, with small leaves densely distributed along

the culm. It is an attractive groundcover that can even be mowed like a lawn. Shibataea kumasaca has short wide leaves, an unusual shape for bamboo, offering an alternate look and texture.

Shrub bamboos Although

more commonly grown

as groundcover plants, several of the dwarf

bamboos, such as Pleioblastus chino var. vaginatus {. variegatus and Sasaella masamuneana ‘Albostriata’, are capable of growing to a larger shrub size. Shrub bamboos typically have reach

a maximum

4 in. (2 cm), but

height of less than

2 in. (1.25 cm)

10 ft. (3 m). Culm

diameter can

is a more typical maximum.

This category includes a number of very large-leaved species with a tropical

appearance, such as Sasa palmata and Indocalamus tessellatus. The latter has the largest bamboo

leaves in cultivation,

up to 2 ft. (0.6 m) long and 4

Pleioblastus pygmaeus var. distichus with fern and rock wall.

in. (10 cm)

wide.

On the left, a Sasa species forms a shrubby border at Hakone Gardens.

184

Chapters These and many others in the shrub category are also aggressive runners. Their growth must be effectively controlled or limited, or they will become very large shrubs indeed. Branching, culm size, and leaf habit vary among species in this group,

providing several different effects. The substantial culms and semi-erect

leaf habit of S. palmata convey

the look of a woody

shrub,

with the culms and

branches readily visible. The large, drooping leaves of /. tessellatus, however, obscure the culm and stems, creating a more rounded, bushy effect. The larger culms and leaves exclude most shrub bamboos from use as groundcovers in the landscape, though many are groundcovers on a larger scale, as ubiquitous understory plants in native forests. In typical landscaping settings, shrub bamboos are often at their best when their circumference is limited to form shrublike shapes, or as hedges, or as accent plants along a stream or contour, Many make excellent container plants and can be used as a low screen on a deck or bal-

cony.

Small-sized bamboos Small-sized bamboos

range

in maximum

height

from

10 ft. (3 m)

up to 20 ft. (6

m), with culm diameters of up to 2 in. (5 cm) or more. In many ways, this size cat-

egory encompasses the greatest diversity of bamboo types. In the United States, Pseudosasa japonica is among the most commonly available bamboo in this size range. The small-sized bamboos also encompass most of the Old World’s pachymorph

“mountain”

bamboos,

such as those from the genus Fargesia, with

their

small, delicate leaves and gracefully arching culms. Also in this category are many of the New

World’s Chusquea, as well as Arundinaria gigantea at its typical height,

the American native that once sprawled across vast areas of the Southeast. A few of the smallest species in the larger running and clumping genera begin to show up in this size category, such as Phyllostachys humilis and some of the Bambusa multiplex cultivars. Very few pachymorph bamboos are hardy, but most of those that are hardy are found in this size category. Unlike most tropical pachymorph bamboos, which, as a group,

have relatively large leaves, most of the hardy pachymorph

have small, delicate leaves. Fargesia nitida,

a montane

pachymorph

bamboos bamboo,

is

among the hardiest of all bamboos. Some

erect running bamboos,

such as Phyllostachys humilis, make

excellent

hedges or screens along a property line. Many of the small pachymorph bamboos, such as most Fargesia, arch too strongly and grow too slowly to make an effective

hedge or screen along a perimeter, unless the space available is generous, but they

©

8= 3 8 © &sg g 12®

=

i= 3

o

E

2 em 2 2

186

Chapter 5

are beautiful specimen plants and attractive “spot screens,” such as one might want for blocking the view from a neighbor’s window.

Medium-sized bamboos Medium-sized bamboos range in maximum

height from 20 ft. (6 m) up to 50 ft.

(15 m), with culm diameters of up to 3 in. (7.5 cm) or more. This size category includes the majority of species in Phyllostachys, the genus of the classic hardy “tree” bamboos. Other hardy genera represented

here include Arundinaria, Semiarundi-

naria, and Sinobambusa. Hardy pachymorph

bamboos are virtually absent from

this category, but semitropical and tropical pachymorph bamboos are well represented, including species of Gigantochloa and many species and forms of Bambusa. Bamboos in this category tend to be more uniformly upright rather than weeping,

but significant variation exists, even within the same genus. Phyllostachys nigra often exhibits a pronounced arching tendency, as contrasted with others of the genus, such as P. bissetii and P. atrovaginata, which are more stiffly upright. Medium-sized bamboos are among the most useful for creating screens. Although they would seldom reach their maximum height in a narrow strip or small grove typical of a screen planting in a garden, they nevertheless rapidly reach a significant portion of their maximum

height. Medium-sized bamboos make excellent

one-story-high screens and, depending on conditions, can make excellent twostory-high screens as well. Although they are capable of substantial height, medium-sized

bamboos

can also be pruned to form a hedge of 10 ft. (3 m) or less.

Since medium-sized running bamboos spread rapidly, they are useful in quickly establishing a screen along a perimeter. These plants readily meet diverse landscaping needs.

A mature clump or grove of medium-sized bamboo establishes a substantial presence that lends itself well to a specimen planting. Enhancing this prospect, many bamboos in this size category have strikingly colored culms, such as the green culms and yellow-striped sulcus of Phyllostachys aureosulcata, the yellow culms and green-striped sulcus of P. bambusoides f. castillonis, the multiple stripes of

Bambusa multiplex ‘Alphonse Karr, or the striking black culms of P. nigra and Gigantochloa atroviolacea. Although

some smaller bamboos

produce good-quality edible shoots, their

smaller size makes them less desirable for shoot harvest. Many

medium-sized

bamboos are prolific producers of relatively large, choice tasting shoots, including Phyllostachys praecox, P. dulcis, P. rubromarginata, and P. iridescens. Once the plant is established in the landscape,

only a few shoots are needed

The “extra” shoots are a boon for the table.

for culm

replacement.

Shown at Hakone Gardens in the fall, Semiarundinar the large culms of the timber bamboo Phyllostachys vivax, to the left

188

Chapter

5

Timber bamboos Timber bamboos have

a maximum

height of up to 100 ft. (30 m) or more, with

culms up to 12 in. (30 cm) in diameter. These giant grasses are the classic tree bamboos. In their native environments, they form not just groves, but true forests that dominate the landscape.

Within this size category, large-leaved semitropical and tropical pachymorph bamboos are predominant

in both size and numbers. Some authorities assert that

a clumping growth habit, large leaves, and large-sized culms are among the indicators of more primitive forms. For humankind,

however, the largest bamboos

are the most useful. For many cultures, these towering grasses are the fiber of life. Once shunned as irrelevant to modern, technology-based economies, these enduring grasses are gaining new acceptance as potentially major players in our modern world. Among the species of pachymorph timber bamboos are Bambusa bambos, B. tulda, Gigantochloa pseudoarundinacea, Guadua angustifolia, and Dendrocalamus

giganteus. This last species is probably the world’s largest bamboo, reaching

a height of 100 ft. (30 m) or more and a culm diameter of 12 in. (30 cm). Its leaves can be up to 20 in. (50 cm) long and 4

in. (10 cm) wide.

Of the hardy, leptomorph bamboos, only Phyllostachys can hold claim to membership in the timber bamboo category. The smaller timber bamboos in the genus

include P. nigra var. henonis, P. makinoi, and P. rubromarginata. The larger ones include P. bambusoides, P. vivax, and the world’s largest hardy timber bamboo, P. heterocycla {. pubescens, which reaches a height of 90 ft. (27 m) and a diameter of 7 in. (18 cm).

Timber bamboos are the bamboos of choice for tall screens, whether for twostory houses or towering apartment buildings. Leptomorph bamboos can rapidly fill a large area and can form a walk-through

forest given the time and space. Pa-

chymorph varieties with a caespitose habit less readily fill an area, but they are more self-contained, and the clumps form an impressive fountain of large culms. Climate generally dictates whether

pachymorph

or leptomorph

varieties can be

planted, but in some climates, such as in the more southerly coastal parts of the United States, selected species of both types may thrive, offering additional interest in the landscape as the often larger leaved pachymorph

bamboos contrast with

the smaller leaved leptomorph species. Typically, timber bamboos in cultivation will not achieve the towering height of a native forest habitat, but they can achieve a formidable height and presence nonetheless. Phyllostachys heterocycla f. pubescens, however, is particularly difficult to establish and is likely to be outgrown, especially in the early years, by many spe-

Landscaping and Maintenance

cies of the same genus with a smaller size potential. Even after a half dozen years or more, the prospects may seem doubtful. Although the potential is there, P. heterocycla {. pubescens may ultimately gain no more stature than that of a medium-sized

bamboo—although vivax, a

a highly attractive and desirable one.

A much

safer bet is P.

very hardy, fast-growing giant with good tasting shoots. Weak culm wood

is its only major drawback,

but

this is less important

in a landscaping situation.

Phyllostachys bambusoides is somewhere in the middle: reliable, but much slower to develop than P. vivax. In some ways

P. bambusoides is the inverse of P. vivax, in that

its culm wood is exceptionally strong, but its shoots are somewhat bitter. Not

unexpectedly,

timber bamboos

are not the best choices

for hedges,

but

height can be controlled by limiting water and fertilizer. Top pruning is another op-

3 In the bamboo

Ba

7s

ae

garden at Hakone Gardens, a variety of sizes and shapes comprise a richly tex-

tured landscape, highlighted by the large grove of Phyllostachys heterocycla f. pubescens in the background.

189

190

Chapter

5

tion and can usually be accomplished without significantly detracting from the aesthetics of the bamboo. With top pruning, it is possible to limit height, yet preserve the striking contrast between

the delicate leaves (especially in species of

Phyllostachys) and large culm diameter.

Climbing bamboos The other size categories have been defined primarily by maximum height. With respect to climbing bamboos, this criterion alone would be quite deceptive. Chusquea valdiviensis, for example,

clambers to a height of 30 ft. (9 m), but its characteristics

are far different from medium-sized

bamboos

of a similar or even lesser height.

Other climbing bamboos include C. uliginosa and Rhipidocladum racemiflorum. These bamboos attain their height by clambering up trees or other tall supports. They are not treelike themselves,

in the manner of the medium-sized

and timber bamboo

“tree grasses,” but rather, they depend on trees for their height and support.

Most climbing bamboos do not have a true vining habit, with culms twining around a support, but the Old World tropical genus Dinochloa offers an exception.

Many climbing bamboos begin growth with a semi-erect, arching habit, but soon droop under their own

weight

to the nearest support. Much

like other plants of

this nature, they may be variously regarded as obnoxious weeds or highly decorative plants. Climbing bamboos have been cultivated only recently in the United

States, but they offer yet another application for bamboo in the garden and landscape. Some are quite beautiful, but many require a tropical or warm subtropical climate, and thus are unsuited to most of the U.S.

Creating Screens and Hedges In the preface to this book I described how I first became interested in bamboo when

what was a greenbelt of large trees, natural vegetation, and wildlife, which

was the extension

of my

backyard,

precipitously became

a treeless wasteland

sprouting two-story homes. My privacy devastated, I desperately went looking fora tall, rapidly growing, evergreen screen. I found a large, costly, non-evergreen

maple with an expansive habit that was wholly unsuited to the fence line in my narrow backyard.

I bought

it anyway

and

had it delivered.

I also purchased

an

attractive ornamental spruce that was equally unsuited to the space. It did not help that the spruce was also a slow grower, nor did it help that it was very heavy for its modest size, and that I injured my back planting it, and that I was not able

to sit upright in a chair for many days afterward.

Landscaping and Maintenance

On a whim, I visited a bamboo nursery, saw stunningly beautiful arborescent bamboos, and listened to the scarcely believable growth claims made by the nursery assistant. I bought bamboo. Over the next several years, I kept careful growth records. Under my enthusiastic but amateur care, the most vigorous species did not quite achieve the yearly doubling of height that was suggested by the nursery assistant—but the growth rate was not too far from the mark. I had purchased vigorous plants in 5-gallon (19-liter) containers. The following year, the bamboo was tall enough to screen me from the first-story windows of the new suburban homes. The next year, the second-story windows were partially screened. By the third year after planting, the second-story windows were completely screened. The fourth year, I started topping the bamboo,

limiting its height, but still benefiting from the impressive look

of the large-diameter culms. Although bamboo is considered the world’s fastest growing plant (not counting giant oceanic kelp, which is not very effective as a residential hedge or screen),

we must remember that maximum growth rate is a function of climate and matching species to the climate.

A bamboo grower in New England would not likely ex-

perience the same rapid growth that I did in my Pacific Northwest environment, whereas a grower in parts of the southern United States can find species that will

create a screening hedge even more rapidly and taller in their climate. In the coldest and snowiest parts of the country, one may need to make do with bamboo screens that are less tall and perhaps only seasonal, if the leaves and culms die back each winter, or if they are weighted down by the snow in winter. Nonetheless, even in the most difficult climates, bamboo is a remarkable landscape plant. Because my backyard is narrow, I do not have the luxury of creating a bamboo grove. The bamboo

runs along my fence line, and I have purposely limited its

width. In some places, the culms emerge in an area less than | ft. (30 cm) wide. In other areas, the width is up to 3 ft.

(1 m). Bamboo branches readily take to prun-

ing, so their expanse can also be limited to a narrow width if desired. Consider this: depending on climate and species, if the total planting area is sufficiently large, as it generally would be running along the perimeter of a residential lot, in only a few

years’ time, you can have a highly attractive, two- or even three-story, evergreen screen in a space only 2 ft. (0.6 m) wide.

As discussed under “Controlling Spread” earlier in the chapter, if one is growing leptomorph bamboos (or pachymorph bamboos with a diffuse habit) along a fence line, a barrier is essential. A barrier offers additional advantages in some in-

stances: since bamboo’s expansive and hungry root system is confined along with

19]

192

Chapter

5

the rhizomes, it is possible to grow a wider variety of ornamentals or garden vegetables at the foot of the bamboo. For tall, narrow hedges, select bamboos that have an erect growth habit. For shorter hedges, it is sometimes possible to use bamboos that are inherently less erect. If culms are topped, they have far less of a tendency to lean, and when allowed to grow closely together for a hedge, the intertwined branches further support the culms. Treated in this manner, bamboos with a normally leaning habit can form stiffly erect hedges. Large arborescent bamboos are usually devoid of branches on the lower portion of their culms, growth

although

this varies among

species. Indeed,

habit that creates their treelike appearance.

The growth

it is partly this habit

usually

works quite well if a solid fence blocks the lower view, but can be less than opti-

mal if there is no solid fence, or ifa more complete barrier is required. In this instance, bamboos with ample branching on their lower nodes may be the bamboos of choice, such as Phyllostachys aurea, with its compressed

lower internodes and

corresponding dense branching at the lower nodes. One can have a visual barrier to ground level, yet maintain the arborescent look by allowing the culms on the outside of the screen to branch closely to the ground, while pruning the branches from the lower nodes on the culms in the foreground view. If sufficiently vigorous, the arborescent habit of some of the large timber bamboos may outgrow their ability to provide effective screening at lower heights. If a large timber bamboo ceases to develop branches at the lower nodes, such that the first branches and leaves are well above the fence line, it may be necessary to interplant a smaller

species to provide the screen near the top of the fence. Alternatively, severing the rhizomes near some of the culms will cause the newly created smaller plants to put forth smaller culms with more branching at the lower nodes.

Interplanting different species can be a useful practice for other reasons as well. Ifa hedge composed of a single species flowers, part or all of the foliage may

be lost, as will be the bamboo’s ability to provide an effective screen, and the entire hedge will be severely weakened or may die altogether. If at least two species

are interplanted, the species that is not in flower can continue to provide foliage and an effective screen

while the flowering species recovers or is replaced. The

species can be similar, such as Phyllostachys nuda and P. bissetii, so that it is scarcely noticeable to the casual viewer that the hedge consists of more than one species, or the species can be dissimilar, with contrasting foliage variegation or culm coloration, such as the black culms of P. nigra intermingled with P. aureosulcata f. spectabilis with its yellow culms and green sulcus, offering a striking appearance.

Landscaping and Maintenance In some instances, it may be desirable to stake bamboo or tie it to a support to prevent a culm from drooping excessively. Or, a culm can be tied to a fence post or other support, pulling it to one side or another to better position it for screening. Caution is in order, however, if the bamboo will be subject to strong winds or snow.

Staking or tying a culm effectively limits its ability to bend under stress. A bamboo that would otherwise bend to the ground under heavy snow, and then return erect with the snowmelt, may snap and break if denied its full range of compliant bending.

wad

NP

ae

Nee

a

View from the rooftop. From the living quarters, all windows of the adjacent home are screened. The bamboos are along a fence line, contained by black plastic barriers. On the far left, Phyllostachys vivax has been topped to limit its height. Phyl/ostachys viridis ‘Robert Young’, to the right,

grows more slowly in the cool Pacific Northwest, but its continued development will be encouraged so that more of the adjacent home will be screened. Phyllostachys bambusoides is next to

the right. It has roughly the same size potential as P. vivax, but it develops more slowly. Next to the right, P. nigra has been topped to permit a distance view and reduce its arching habit, which would intrude into the sunlight for the garden. At the far right, container bamboos provide additional privacy screening as desired.

193

194

Chapter

5

Hedges are effective barriers against strong winds, shielding the home and protecting the more delicate parts of the garden. Ironically, the most effective barrier for most purposes is one that allows some air passage. Solid barriers, such as walls, create air turbulence on the leeward damage in affected areas.

side, potentially causing

havoc and

A bamboo hedge will block some air passage and diffuse

the air that does filter through, avoiding the turbulence problems of a solid barrier. Shrub or groundcover bamboos that are not clipped, but allowed to grow taller, also make excellent hedges when a low screen is required, or when one wants to deter the path of people or animals. More closely clipped groundcover bamboos make excellent borders, attractively delimiting an area, or deflecting the paths of small animals. Bamboos

in containers offer additional options for creating portable screens.

Bamboo is very light for its size and grows well in containers. If a new planting of bamboo,

or existing or recently removed

screen, a container of bamboo

vegetation, is not providing the desired

be can be strategically moved

into place to fill the

need. A heavy snowlall once snapped the young culms of part of the bamboo screen along my fence line. I moved

container bamboos in place to temporarily replace

the broken screen while awaiting the shooting season and growth of the new culms that would replace those that had snapped. Container bamboos, as mobile

screens, can come into play in a wide range of scenarios. A less hardy bamboo can be grown in a container to provide a supplemental screen or shade for the patio in

the summer, then moved to a more protected area for the winter. A deciduous tree in full leaf, but can be supplemented with container bamboo in the winter months—perhaps a container bam-

or shrub may provide the desired screen when

boo that had been providing shade or additional screening for the patio in the summer months. A container of bamboo

can provide an excellent screen for the

deck or lanai of the apartment or condominium

dweller, bringing

a welcome

touch of the garden in the process. These are but a few examples of ways that container bamboos container,

bamboo

can be used as portable screens. Both is a superb

evergreen

screen.

in the ground and

in

CT AUPE

Re 6

Bamboo Uses

THE

SUBJECT

OF BAMBOO

USES can readily fill several volum

Though

it is

not the focus of this book, I would be remiss if I did not touch on the subject at least briefly. From an economic standpoint, bamboo is popularly associated with Asian cultures and economies. The enhancement of bamboo resources for traditional uses remains an important means of improving the general well being of many peoples, and it will likely remain so for a good long time. Runaway population growth, and

the absence

of adequate

management

of bamboo

resources,

increasingly

threaten bamboo and jeopardize the populations that depend on it.

While it is important not to ignore the continuing role of bamboo in traditional economies,

it is equally important

not to assume

that bamboo

has little

place in our modern economies. The first commercial light bulbs were made from bamboo fibers, then the only material found suitable for the task. Today, bamboo fibers offer advantages over synthetic fibers and other organic fibers in the man-

ufacture of sophisticated structural composites.

Bamboo in Traditional Economies In The Bamboo Garden, published in 1896, A. B. Freeman-Mitford describes some of bamboo’s traditional uses in China and Japan. An excerpt from his lengthy de-

scription illustrates bamboo’s pervasive importance in the culture and economy of those countries.

195

196

Chapter 6

The Bamboo is of supreme value; indeed, it may be said that there is not a necessity, a luxury, or a pleasure of his daily life to which it does not minister. It furnishes the framework of his house and thatches the roof over his head, while it supplies paper for his windows, awnings for his sheds, and blinds for his verandah. His beds, his tables, his chairs, his cupboards, his thousand and one small articles of furniture are made of it. Shavings and shreds of Bamboos are used to stuff his pillows and his mattresses. The retail dealer’s measures, the carpenter’s rule, the farmer’s water-wheel and irrigating pipes, cages for birds, crickets, and other pets, vessels of all kinds, from the richly lacquered flower-

stands of the well-to-do gentleman down to the humblest utensils, the wretchedest duds of the very poor, all come from the same source. The

boatman’s raft, and the tool with which he punts it along; his ropes, his mat-sails, and the ribs to which they are fastened; the palanquin in which the stately mandarin is borne to his office, the bride to her wedding, the coffin to the grave; the cruel instruments of the executioner,

the lazy painted beauty’s fan and parasol, the soldier’s spear, quiver, and arrows, the scribe’s pen, the student’s book, the artist’s brush, and the favorite study for his sketch; the musician’s flute, mouth-organ,

plectrum, and a dozen various instruments of strange shapes and still stranger sounds—in the making of all these the Bamboo. In China’s Henan Province, excavated ruins dating from the Yin Dynasty, in the 16th to 11th century B.c., revealed bamboo winnowing implements, ji, and arrow containers, fu, in the writings on bones and tortoise shells. A collection of poems from the early years of the Western Zhou Dynasty that dated from the 11th

to 5th century B.c. include references to eating bamboo shoots. In China’s Zhejiang Province, the excavation of 5000-year-old ruins revealed baskets, mats, and other articles woven

from bamboo.

At least as early as the spring and autumn

period

(770 to 476 B.c.) of the Western Zhou Dynasty, historical and cultural events were carved on bamboo splits, zhu-jian. Bamboo papermaking began during the West-

ern Jin Dynasty in the 3rd century. By the 17th century A.D., some 960 characters contained bamboo radicals, a testimony to the importance of bamboo and its integral role in culture and daily life (Chen and Chia 1988; Wu and Ma 1985). In the 11th century A.D., Su Dongpo, a famous Chinese poet of the Sung Dynasty, proclaimed:

Banboo Uses

There are bamboo tiles for shelter, bamboo hats for shading, bamboo paper for writing, bamboo rafts for carrying, bamboo skin for clothing,

bamboo shoes for wearing, bamboo shoots for eating and bamboo fuel for fires. Indeed, we cannot live without bamboos for a single day (Wu and Ma

1985).

In the Western world, to the extent that we think of it at all, we tend to view China’s extensive bamboo forests as a natural phenomenon, but many of China’s great forests are the result of human

intervention and conscious management.

China’s active reforestation projects began more than 500 years ago, when some of the dynastic emperors undertook massive bamboo reforestation programs. As much as a thousand years ago, many of China’s natural tree forests had been clearcut or severely decimated. The emperors saw bamboo as a way to reclaim the once-forested lands. Even in the New World, humankind’s association with bamboo has a lengthy

history. The earliest evidence, so far, dating to roughly 3500 B.c., are fragments of walls, in Valdivia, Ecuador, made from Guadua and mud. Like the Proto-Malays of what is now Indonesia, who are believed to have actively and systematically cultivated bamboo thousands of years ago, ancestral indigenous peoples of the western Amazon basin are believed to have cultivated bamboo, resulting in some of the bamboo-dominated areas currently found in the region (Judziewicz et al. 1999).

Bamboo in Modern Economies A relatively early meeting

of bamboo

and technology occurred

in the develop-

ment of the light bulb. In the latter half of the 19th century, Thomas Edison conducted some 400 experiments to find a material suitable for a light bulb filament, without success. Discovery of a suitable material came unexpectedly in 1878, when Edison and a group of scientists gathered at a site in Wyoming to observe the

eclipse of the sun. While camping, a bamboo fishing pole was accidentally knocked into the campfire. Observing that the bamboo did not disintegrate, Edison began

experimenting with bamboos upon return to his New Jersey laboratory (Shor et al. 1996). After extensively evaluating bamboos from throughout the world, Edison selected a variety from Japan. In 1882, he established a company to produce incandescent lamps using bamboo filaments. The world’s first commercial light bulbs used filaments made from carbonized bamboo.

Although eventually re-

7,

198

Chapter 6

placed by tungsten, literally millions of bamboo filament bulbs were produced, illuminating the night with this defining technology. As the population density on this finite planet increases with headlong rapidity, the world’s forests are diminishing at a similar pace. The forests that remain are often overstressed and overused. The wood forests of Europe and North America

have suffered a long decline that has accelerated in recent years. In some regions of the United States, the forest-products industries and local economies, as well as the forests themselves, are at risk. Alternative wood and fiber sources are needed to supplement or replace the wood-forest

resource. In the future, and out of ne-

cessity, fiber composites will increasingly replace wood boards in construction. Facial tissues, boxes, and writing paper will increasingly come from nonwood fiber sources. Bamboo is among the more promising sources of fiber. Unfortunately,

just as the world’s wood

forests have been decimated

demands of expanding populations, so too have the world’s bamboo

by the

forests. Un-

like the wood forests, bamboo’s rapid regenerative ability lends itself to intensive, ongoing harvest and use—at least as long as good management practices are observed. Bamboo can also be planted and harvested as an agricultural crop. It often

thrives in marginal use areas unsuitable for other crops. Aside from the elimination of bamboo

lands to make

room

for more people, bamboo

resources are fre-

quently at risk today because bamboo has simply been taken, without regard to maintaining it as an ongoing resource. In 1952, over 70 percent of India’s paper production came from bamboo; by 1980, only 30 percent came from bamboo. Al-

though the percentage decrease was partly attributable to increased paper consumption, a shortage of bamboo and the failure to restore and maintain decimated plantations and natural stands played a significant role in the decline. Once associated solely with traditional cultures and undeveloped economies, the value of bamboo

transcends all cultures and all economies.

In developing

economies, it is a bridge between the traditional and modern. While some economic policies have been quick to abandon bamboo as representative of the past, other more enlightened policies have initiated intensive research and development programs. China has long recognized the importance of bamboo in a modern economy. Even as the nation’s economy becomes more mechanized and industrialized, bamboo remains an emphasis. As in many areas of the world, some of China’s bamboo lands and forests have diminished under population pressures. The plains along the Chang River Valley, for example, were once densely covered with bamboo and other forests, but these have been reduced to small areas around homesteads. At the same time, China’s active development

practices increased

Bamboo Uses

the acreage of Phyllostachys heterocycla f. pubescens, a commercially highly valuable

bamboo for both food and fiber, from approximately 3.5 million acres (1.4 million hectares)

in 1950 to more

than

7 million acres (2.8 million

hectares)

by

1987.

Today, P. heterocycla £. pubescens accounts for more than two-thirds of China’s im-

mense bamboo acreage. As important as bamboo

has been to both the traditional and modern

econ-

omies of Asia, India, and other regions where bamboo is a prominent native plant, its commercial capabilities have never exported well. In Europe and the United States, bamboo

has found hospitable growing climates, yet it rarely plays a role

other than as a garden ornamental. The frustrations of bamboo’s early advocates are evident in the commentary of A. B. Freeman-Mitford in The Bamboo Garden

(1896):

It is to be regretted that, however well we may succeed in the cultiva-

tion of Bamboos for pleasure and ornament, the plant which is so rich in economic value in its own country is not likely to prove useful here. I consulted a leading London

umbrella and stick maker on the subject,

and he told me that in his trade they were obliged even to eschew the canes of the South of France as insufficiently ripened, and consequently liable to split. It would seem, then, that we must be contented with the beauty of our plants and ask no more of them than they can

give; but itis hard to think that out of so much wealth we cannot even achieve the humble triumph of an umbrella stick.

Efforts in America have suffered similar frustration. After nearly three-quarters of a century, the United States Department of Agriculture ceased large-scale bamboo

research in 1965, then in 1975, stopped its program

of importation and

introduction of new bamboo plant materials from foreign sources. Bamboo is unlike any other of the West’s familiar agricultural

plants, and its acceptance

has

been hard in coming.

Pulp and wood In the United States, the first comparative yield assessments of bamboo

and the

more traditional sources of pulp were made in 1966. Loblolly pine, Pinus taeda, and

the bamboo Phyllostachys bambusoides were chosen for the comparison study. The species were planted in adjacent plots in 1959. For the test, strips were cut from the test plots, the bark was removed moved

from the loblolly pine, and

the leaves re-

from the bamboo. The wood was oven dried, then weighed. The bamboo

199

200

Chapter 6

yielded nearly twice the weight of the loblolly pine. In addition, and unlike loblolly pine, bamboo has the capacity for rapid regeneration from its rhizome system. In separate tests, other bamboo species produced yields of more than double those of

P. bambusoides, compounding the potential advantage of bamboo. The study report further indicated that bamboo fiber has a much greater length-to-width ratio than pine, allowing the final product to be more pliable, softer, and smoother—a benefit in such items as facial tissue and writing paper. The comparative yield study with loblolly pine demonstrated the superiority of bamboo

in key aspects of fiber production.

Regrettably,

further studies were

ceased for want of funding. Before bamboo can be fully compared to other competing wood

and

fiber sources, more studies are needed

to determine optimal

growing and harvesting regimens, cultivation and harvest methods suitable to mechanized economies with high labor costs, expected ongoing yields for established groves, and other related concerns. The extensive research

in China and

other countries must be supplemented with additional research germane to Westerm economies.

In China,

bamboo

is harvested

and sorted according to size and quality.

Among the best quality culms, the larger ones are used for flooring, the smaller for

weaving. Bent culms and tops of culms are used for chipboard,

a bamboo product

that is similar to plywood. Lesser quality bamboo goes into pulp production. The best quality culms command the highest prices, but maximizing the yield of the highest quality culms and selectively harvesting and processing them labor-intensive process. What

makes economic sense in less mechanized

is a

econo-

mies with a lower wage scale may not work as effectively in a highly mechanized economy with a much higher wage scale. In economies such as that of the United States, producing quality culm wood competitively in the world market might be

a difficult proposition, but the production of pulp, chips, and chipboard much more readily lends itself to the efficiencies of technology and mechanization.

general, as economies become

more

modernized and mechanized,

In

the use of

whole culms declines, and the use of processed bamboo increases. In America and much of Europe, trees are broadly regarded as the sole source

of fiber for pulp and paper. Much of the rest of the world has never had access to vast forests of inexpensive trees and has always relied on other sources of fiber. Now that the Western world is increasingly coming hard against the limitations of forests that are rather less vast and increasingly overstressed,

the prospect that

there are other effective fiber sources comes as something of a surprise. Nonwood

sources of fiber can be broken into four broad categories: seed hull

Bamboo Uses

fibers, such as cotton; leaf fibers, such as sisal, abaca, and palm; bast fibers, such as flax, hemp,

and jute; and culm

boos. Most nonwood

fibers, such as cereals, grasses, reeds, and bam-

fiber crops grow in semitropical or tropical environments,

but some are adapted to the temperate climates of the United States and Europe. The American West and Mediterranean Europe, however, also incur the additional limitation of minimal precipitation or of precipitation that comes predominantly at times other than the growing season.

Flax is an example of an alternate fiber source that produces high-quality fiber but relatively low yields per acre. In the United States, flax finds its way into paper as a harvest byproduct. After oil seed flax is combined, the “waste straw” is baled and shipped to paper mills. Hemp, quality fiber. In 1989, the European

Cannabis sativa, produces high yields of highEconomic Community

for industrial hemp that is certified low in THC

established subsidies

(the psychoactive substance in

marijuana). It remains illegal to grow any kind of hemp in the United States. Kenaf

(Hibiscus cannabinus) produces high-quality fiber but requires warm growing conditions and ample moisture to achieve high yields. It is best suited to regions approximating semitropical conditions with

high summer

rainfall or ample irriga-

tion. Waste straw from grain production is a low-cost fiber source, but high silica

content and the tendency to retain water is detrimental to milling processes. Hybrid poplar (Populus trichocarpa x P. deltoides) is a conventional wood fiber source that can be managed unconventionally and treated more like an agricultural crop. The Pacific Northwest has had extensive test acreage planted since the 1960s. Hybrid poplar propagates easily from cuttings and has an 8- to 10-year harvest rotation. It is shallow rooted, however, and requires intensive management and weed suppression if its yield potential is to be realized.

The preceding examples are only a very few of the world’s possible fiber sources, but they illustrate a range of options that pulp and fiber industries situated

in temperate climates may consider when confronted with the need to supplement or replace traditional wood fiber resources. Another alternate fiber source is bamboo. Bamboo is a high-yielding perennial that produces very high quality fiber, can

be harvested on a needs basis rather that at a narrowly defined harvest period, and can regenerate rapidly. Approximately

4 tons (3600 kg) of fresh culms are re-

quired to produce one ton (900 kg) of unbleached pulp. It is a highly productive, advantageous source of fiber, but it has a few disadvantages as well. Like other grasses, bamboo’s high silica content is a disadvantage in pulp and paper manufacturing. High silica content causes problems with chemical recycling and im-

201

202

Chapter 6

pedes the papermaking process. Wood, bast fibers (such as flax, hemp, and kenaf),

as well as some other fiber sources, have little or no silica. Maximum fiber content is reached by the time a bamboo culm is one year old, but lignin and silica, unde-

sirable elements

for pulp and paper, continue to increase. For these reasons,

younger culms are preferable for pulp and paper (Fu and Banik 1996). Both China and India extensively use bamboo as a fiber source for paper manufacturing. Bamboo was first used in India as a source of paper pulp on an experimental basis in 1923. Now, nearly two-thirds of India’s annual bamboo production is consumed

by the papermaking

industry. Since bamboo

harvesting is not

necessarily confined to a narrow season, many Asian mills use bamboo when other seasonal fiber sources are unavailable. Traditional papermaking on a small scale is still practiced in the Chinese countryside, but modern paper mills geared to pulp supplied by bamboo have also been established in China. The relevance and importance of bamboos to modern technologies remains largely unrecognized. The role of bamboos in structural composites illustrates a facet of bamboo’s potential. Bamboo poles, strips, and fibers offer potential strength, weight, and cost advantages over the synthetic reinforcing

fibers used in struc-

tural composites. An extrusion incorporating bamboo culms and recycled plastics

(including recycled garbage bags, milk jugs, disposable diapers, and the like) can produce telephone poles that are stronger, lighter, and less costly than conventional wood poles—and they do not further tax declining harvestable timber resources.

In more sophisticated applications, bamboo fiber and plastic resins can be used to produce dimensional lumber that can replace wood in housing construction. In other applications, because of bamboo’s cost advantages over synthetic fibers, composites made with bamboo may become cost-competitive with concrete for highway bridges and other similar uses, while offering structural benefits superior to conventional concrete construction. Development coming,

but bamboo

has been slow and long in

holds great potential for structural composites and other

technological applications. Forage Bamboo leaves can provide excellent animal forage. Although the giant panda’s penchant for bamboo is well known, it is not common

knowledge that bamboos

are a desirable forage for many animals. The consumption of bamboo leaves by an-

imals other than pandas, and as livestock forage, is often overlooked—though not by the animals. Some Himalayan bamboos almost never achieve full height in their native environments because indigenous animals browse them so heavily.

Bamboo Uses

In Oregon, bamboo grower Garold Nelson noted his cattle’s enthusiasm for bamboo leaves when he began feeding them prunings from his bamboos. This observation prompted additional experimentation, funding from regional chapters of the American

Bamboo

The tests showed

Society, and the involvement of Oregon State University.

that although bamboo leaf samples had a significantly lower percentage of dry matter digestibility than alfalfa, it was generally similar to other

common

hay crops. This suggests that, although

bamboo

leaves may

not be an

ideal feed for dairy cattle, they would be quite suitable for beef cattle, horses, sheep, and goats. The protein content of bamboo leaf forage also was found to increase toward winter, a time when other common

forages decrease in protein con-

tent. Included in the testing were species of Hibanobambusa, Phyllostachys, Pleioblastus, Sasa, and Semiarundinaria. Of more than 10 species evaluated, all tested well (Nelson

1997).

One can readily envision a scenario for seasonal utilization of a temperateclimate bamboo grove. Fresh shoots are harvested in the spring. During fall and

winter, the normal harvest season for mature culms, the leaves from the harvested culms are also used, as a high-protein winter forage.

Food In Thailand, China, Japan, and Taiwan, more than a million tons of bamboo

shoots

are harvested every year. In China alone, more than 100 kinds of bamboo shoots are harvested for food. The Chinese bamboos most often cultivated for shoots include Phyllostachys heterocycla {. pubescens, P. praecox, P. dulcis, and P. iridescens. Phyllostachys heterocycla {. pubescens and P. praecox are exceptionally productive, yielding

between 8 and 12 tons of fresh shoots per acre (20 to 30 tons per hectare). A 1931 Japanese text on the culture of P. heterocycla f. pubescens in Japan des ribes a similar yield, citing a shoot harvest ranging from 3 to 12 tons per acre (7 to 30 tons per hectare), with 8 tons per acre (20 tons per hectare) being the typical yield. An unmanaged stand is likely to produce far less, perhaps under | ton per acre (2'2 tons per hectare).

In Asia, both commercial

shoot

production

as well as the market

for fresh

shoots (and canned and dried shoots) are large and well established. In the United

States, despite some notable exceptions and tentative success stories, the absence of an established market for fresh shoots for the grocery trade, or for processors to can, freeze, or dry, is a disincentive for establishing, maintaining, and harvesting

a shoot-producing grove. At the same time, the lack of shoot producers means that fresh shoots will be unavailable and that no market can be established. Each one needs the other in order to exist. Both the producers and the markets are des-

203

204

Chapter6

tined to be small, marginal, and erratic until and unless a critical mass is reached.

Not unexpectedly, areas of the country with significant Asian populations are the best prospects for establishing a market for fresh shoots.

Eating Bamboo Shoots

In Asia, bamboo shoots are harvested and consumed in great proportions. In the New World’s bamboo-growing regions, shoots play far less of a role as a food item.

Some of the prominent New World tropical bamboos, such as Guadua angustifolia, are very bitter and unsavory. In one region of Colombia, however, the shoots of a

Guadua species are sweetened with brown sugar and consumed as a dessert. At least some New World bamboo shoots can be very good without amelioration. I have eaten Chusquea shoots that were excellent, arguably superior in character to the shoots of most Phyllostachys species.

The shoots of some tropical and semitropical clumping bamboos have notable concentrations of cyanogens prior to parboiling. Examples include species of Bambusa, Dendrocalamus, Gigantochloa, and Guadua, among others (Guala 1993). Not all the species contain cyanogens. Dendrocalamus giganteus, for example, is said to be safe even

when

eaten raw

(Liese

1991). As a precaution,

however,

all semitropi-

cal and tropical bamboo shoots should be parboiled before eating, a process that eliminates the cyanogens.

Parboiling is not a culinary handicap, as the crunchy

texture remains, and the parboiling enhances the flavor of the shoots. Once boiled, some of the same species that have significant cyanogens in the raw state are also among

those regarded as choice eating, and they are cultivated for their shoots.

These include Dendrocalamus latiflorus, Bambusa beecheyana, Gigantochloa levis, and Schizostachyum brachycladum, among many

(Hsiung,

1991).

To reiterate the general rule and precaution, the shoots of tropical and semi-

tropical species should never be eaten raw, unless one has certain knowledge that a specific and accurately identified bamboo is entirely safe. Among the temperate bamboos, Phyllostachys is the predominant source for shoots. All species are suitable for the table, though some are better than others. Phyllostachys nuda, P. platyglossa, P. nidularia, P. dulcis, and P. vivax are among those with excellent tasting shoots. The shoots of P. bambusoides are rather bitter, but

can be tamed by boiling. Species of other temperate genera, such as Semiarundinaria

fastuosa, also pro-

duce fine tasting shoots. Some, like Qiongzhuea tumidissinoda, are considered excep-

Bamboo Uses

205

tional. The quality of the shoots can vary widely within the same genus. Pleioblas-

tus amarus, for example, is considered very bitter and inedible, whereas P. hindsii produces choice tasting shoots. Many temperate bamboo species produce shoots that taste good but are too small to bother harvesting. Bamboo shoots are at their best when harvested young. They taste better and are nutritionally superior. According to a Chinese study, bamboo

shoots have a

higher protein content than any other vegetable. Using Phyllostachys heterocycla {.

pubescens, the study found that protein content was highest in shoots that had not emerged

from

the ground, and subsequently decreased with time out of the

ground, when measured at 5 and 10 days. There are many ways of preparing the shoots to eat. As a first step, the culm leaves can be peeled away from the edible part of the shoot. A quicker and easier

method that I prefer calls for cutting the shoots in half along their length. With the cut face of one of the halves facing you, start to push the tip of the shoot

(which

will be the culm leaf

material) down and away with one hand, while pressing upward from underneath in the middle or upper part of the shoot with the other hand. The tender shoot will separate from the

culm leaves and can then be readily removed. The white or lightly colored bases of the culm

leaves near the tip of the shoot will stay behind. These are also tasty to eat and can

be

ripped away from the less tender portions of the leaf material. The entire operation is quick,

requires little skill or practice, and is much easier to do than to describe. At this point, the shoots can be parboiled and used in a variety of recipes. Some

shoots

are completely free of bitterness and, in the case of temperate-climate bamboos, can be eaten raw (remember the precaution for tropical and semitropical bamboos mentioned earlier). The raw, crisp texture may be desirable for some culinary uses, such as in a salad, but bamboo generally improves in flavor after parboiling.

A freshly harvested Phyllostachys vivax shoot is ready to prepare for the table.

206

Chapter 6 Five minutes is sufficient for shoots that are not bitter. Bitter shoots can be boiled up to 20 minutes or more, Exceptionally bitter shoots should be boiled in one or more changes of water. The shoots can be left whole or in large sections, but if bitter, they should be cut into smaller chunks or slices to allow better contact with the water. Bamboo parboiled

shoots retain a pleasant crunchy texture even after they have been

for some time. After parboiling, the shoots are ready for soups, a light

lacing of soy sauce, grilling on the barbecue, or any of a wide variety of preparations. They

integrate well with many

dishes and readily take on the flavors of

herbs, spices, and foods cooked with them. Bamboo shoots can also be salt-pickled, in the manner of Japanese vegetables, and eaten after a day or two or for up to a month, depending on the flavor desired. Tastes for astringency vary. Some people prefer shoots with a degree of bitter-

a

_.

The edible shoot is removed from the culm leaves by The shoot is cut in half along its length. The segmented structure of nodes and internodes is clearly revealed. The internodes are just

beginning their extension.

pushing the tip of the shoot (which is all leaf material) down and away with one hand, while the other hand presses upward from underneath at the middle or upper part of the shoot. This frees the edible shoot

from the leaf material.

The lowermost portions of the undeveloped

culm leaves, toward the tip of the remaining leaf material, are tender and edible, much like the leaves of an artichoke. If desired, the tender parts can be pulled away and saved

for eating.

On the left, the edible portion of the shoot

after removal from the leaf material. On the

right, the edible portions of the undeveloped culm leaves from the upper area of the leaf material. In the center, the remaining,

ble leaf material.

inedi-

208

Chapter 6

ness for pungently flavored stir-fries or other recipes. The astringently bitter shoots of Bambusa vulgaris are highly regarded in some cultures. Although the absence of bitterness is almost always preferred, astringency can be regulated by the choice of species and length of boiling time. A variety of commercially dried shoots is available. Chinese or other Asian gro-

cery stores are excellent sources. Qiongzhuea tumidissinoda is regarded as a choice shoot for drying, though I cannot say whether or not I have ever had it. I have never found dried or canned shoots that were identified as to the species, though one can sometimes make educated guesses by size, general appearance, and country of origin.

Sliced shoots can be thoroughly dried to the point of hardness, or salted and dried to the point that they are still soft and pliable. The ones that I have encountered that had been dried to the point of hardness require extensive soaking and subsequent steaming, boiling, or cooking in liquid before they can be eaten. Although sometimes very fragrant, they can be problematic to reconstitute satisfac-

torily. Nevertheless, hard-dried shoots can add an excellent flavor to many dishes. I have greatly enjoyed many of the more pliable salted shoots, though quality can

vary widely. I have had some that were bitter, with an unsavory taste and mushy texture. Most, however, are very good, and some are excellent, highly fragrant,

and have outstanding flavor. For a simple and delicious way to explore the salted, pliable, dried shoots, soak them

in water until mostly tender, then put them

in a mixture of sliced beef or

pork, minced ginger, green onion, leek, or shallot, sliced mushrooms, sugar, soy sauce, and sesame oil. Place in an open bowl and steam for 20 minutes or so, until the meat is cooked. Serve with steamed rice. As with most vegetables, canned shoots are inferior to fresh—but they are far

better than none at all. The quality of canned shoots is generally consistent, with a good if somewhat

bland character, but I have encountered

some that were

mushy with little taste. Canned shoots that have been pickled or combined with other flavorings can be very good. The species of shoot is rarely, if ever, found on

the can. Although shoot-producing countries may process

a number of species,

one species usually predominates. China’s canned shoots are mostly Phyllostachys heterocycla f. pubescens. Thailand processes primarily Dendrocalamus asper. In general,

shoots from Thailand tend to be quite good, particularly those that have been salt pickled with additional ingredients. Ihave not included a listing of recipes, as many Asian cookbooks already include recipes with bamboo shoots. In recipes, fresh shoots can be “substituted” for

Bamboo

canned shoots (which are, of course, substitutes for fresh shoots). For a quick way

to sample your harvested shoots, sauté the parboiled shoots with garlic and ginger, adding soy sauce with a bit of sugar to taste. A few drops of sesame oil is also a nice addition. Or, Western style, sauté in olive oil or butter, with some chopped garlic

if desired, and salt to taste.

Other bamboo foods In addition to the shoots, bamboo plants offer other, less common food possibilities. When topped at a height of roughly 3 ft. (about | m), the growing shoots of Oxytenanthera braunii continue to exude sap for many weeks. In Tanzania, the sap is collected and fermented into a wine-like drink called ulanzi. Bamboo

leaves are seldom

eaten, but in rural mountainous

areas of Japan

where Sasa is plentiful, new Sasa leaves are harvested while they are still tightly rolled and light green in color, and are then sautéed. It is a seasonal delicacy served in the local hotels and inns. Bamboo seed is edible like other food grains. It can be consumed

in a variety

of ways: cooked like rice, or ground into a flour to make dumplings, noodles, or gruel. It can be fermented

to make an alcoholic beverage, or roasted to eat as a

snack, or included in pancakes, muffins, or other baked goods. A few bamboos produce fleshy fruits. The indigenous peoples of Peru eat the fruits of Guadua sar-

cocarpa, both cooked and raw. The fruits of Olmeca species are also edible, if not particularly good. Although not a food, per se, large-leaved bamboos are used for wrapping food, the bamboo

leaves containing a natural preservative that helps prevent deterio-

ration. Carrying this theme further, a filling of meat and condiments is placed inside a ball of rice, wrapped in bamboo leaves, and then steamed. The bamboo leaves impart a subtle flavor to the mixture. Rice is also sometimes boiled in the joints of the tropical bamboo Cephalostachyum pergracile, imparting a distinctive flavor and providing a convenient carrying vessel when traveling.

Uses

209

CHARTER

7

Bamboo in America

AMERICA’S

NATIVE CANE Arundinaria gigantea once spanned thousands of acres

from Virginia and Florida across to Texas, north to Missouri, and up the Ohio River Valley. Buffalo migrated through these cane meadows into Kentucky and Tennessee to feed during winter. The canebrakes offered prime hunting ground for local

Native Americans and provided pasture and winter shelter for the livestock of the European settlers. Prior to the Civil War, the canebrakes helped hide slaves escaping to freedom in the North. In spite of its widespread presence in the early days of the United States, bam-

boo was never really assimilated into American culture in any major or lasting way. Bamboo

was something that was used as long as it was around, but it was

never absorbed into life’s fabric, to be cherished, nurtured, and restored. The canebrakes were regarded as indicative of fertile soil, and were thus targeted by the early settlers. Land clearing, fires, flowering cycles, and overgrazing all contributed to the decimation of the once-great expanses of the native cane. Once gone, either intentionally or inadvertently, it was never replaced. For many

people throughout

the world, bamboo

is an intrinsic part of their

lives and their landscape. Its presence, its beauty, and its utility are part of the liv-

ing fabric of the land and the human spirit. But bamboo is virtually absent from European

and American

culture and tradition.

It plays little or no role in the

United States as building material, food, forage, ornamental plant, or anything of significance, except, perhaps, for the occasional garden stake.

210

Bamboo

Utility and beauty are the warp and weft of bamboo culture. One calls for the

other, gives form to the other, sustains the other. For bamboo, if one is after beauty, one also encounters utility. If one is after utility, one also encounters beauty. Societies that have assimilated bamboo into the human spirit know its full fabric. In the

European world and in America, the beauty in the landscape may be a seductive gateway that leads us to consider and explore its utility.

The first foreign species were introduced into the United States when Arund-

inaria gigantea ssp. gigantea and A. gigantea ssp. tecta, the native American cane, still

covered large expanses of land. The very first introduction may have been Bambusa vulgaris, which was cultivated by Spanish colonists in southern Florida in the 1840s. Other sources cite an earlier introduction of Phyllostachys aurea by a Mr. G. H. Todd of Montgomery, Alabama, in 1822. Documentation of subsequent introductions is incomplete, but some that are known include Pseudosasa japonica

in 1860; Pleioblastus simonii to Wallingford, Pennsylvania, in 1876; Phyllostachys

aurea in 1882

(possibly a subsequent

introduction);

Sasa palmata in 1891; and a

grove of P. nigra var. henonis was established near Shreveport, Louisiana, around 1894.

American Researchers and Proponents In 1896, while on a trip to Sumatra, an American plant pathologist, David Fairchild, and his friend and benefactor, Barbour Lathrop, were struck by bamboo’s great beauty and utility. In 1897, Fairchild and Lathrop entered into an informal

partnership to study and seek out plants useful to humankind and introduce them to America. This informal partnership lasted until Lathrop’s death in 1927, and it has been attributed to the introduction of a large portion of the bamboos

in the

United States today.

Under the United States Department of Agriculture (USDA), Fairchild helped organize the Section of Foreign Seed and Plant Introduction and established a formalized method for recording new plant introductions. Beginning in 1898, new bamboos were assigned plant introduction numbers and cataloged in the USDA journal, Plant Inventory. Subsequently, Fairchild held the position of Agricultural Plant Explorer, enabling him to introduce many new bamboos. He was responsi-

ble for establishing a network of plant introduction stations where plant explorers could send Louisiana,

new

introductions.

Maryland,

The stations included

California, and

sites in Florida,

Puerto Rico. The Maryland

Georgia,

site played

major role in the introduction of bamboos into the northeastern United States.

a

in America

211

212

Chapter 7

The plant introduction station near Savannah, Georgia, has a story of its own. Its origins grew out of a decision by a local resident to plant three bamboo plants

next to a well on her property. Planted in 1890, these three bamboo plants were later determined to be the large timber bamboo Phyllostachys bambusoides. By 1915, the bamboo covered approximately an acre (0.4 hectares) and literally surrounded

the property’s two-story farmhouse. Fairchild learned of the 46 acre (19 hectare) farm and, it is said, half jokingly wrote to his friend, Barbour Lathrop, asking him

if he wanted to own a bamboo grove on the Ogeechee River. Lathrop immediately agreed, authorized the purchase of the farm, and presented it as a gift to the USDA Office of Plant Introduction. The station was to play a major role in the introduc-

tion of bamboo in the South and to botanical gardens across America. After Lathrop’s death, the station was named “The Barbour Lathrop Plant Introduction Garden.” For three-quarters of a century, the site has been informally known as the “Bamboo Farm.” Closed by the USDA in 1980, the Bamboo Farm was kept in care-

taker status until 1983, when it was given to the University of Georgia. Throughout its history, the Bamboo Farm has been involved in widely varied research, as well as in applications for private industry and government. Some of these include the use of bamboo as a source of pulp for papermaking by the Champion and Scott paper companies,

bamboo

shoots and water chestnuts for the Campbell

Soup

Company, and bamboo for training purposes during the Vietnam War.

In 1905, Fairchild hired Frank Meyer as an Agricultural Explorer. Although Meyer initiated the introduction of many Chinese bamboos, mishaps and bad luck

prevented the successful introduction of all but a few. One, Phyllostachys meyeri, was subsequently named for him. In another unfortunate turn, Meyer made an extensive search for a new bamboo introduction station, finally settling on a site at Brooksville, Florida, He believed that the site’s clay subsoil was necessary to support tall bamboos. Unfortunately, the clay greatly impeded growth, and heavy rains often turned the area into a swamp. Meyer drowned in China’s Chang River in May of 1918. The Bamboo

Farm

in Georgia became

the replacement

site for

Brooksville, and in the early 1930s, Meyer’s struggling collection of introductions at Brooksville was moved to the Bamboo Farm. Other American bamboo researchers and growers who made notable contributions in the first half of the 20th century include Robert A. Young and E. A. Mcllhenny. Young, through his work at the USDA plant introduction stations, contributed significantly to the bamboo research and literature. A striking and at-

tractive cultivar of Phyllostachys

viridis, ‘Robert Young’ is named after him. Mcll-

henny, of Tabasco sauce and Avery Island fame, was an ardent bamboo grower and

Bamboo in America

advocate. His skills and devotion to bamboo were responsible for the survival of more than one of the new introductions. He wrote popular articles promoting the merits of bamboo. Perhaps the greatest bamboo researcher of all, American or otherwise, was F. A. McClure. Born on a farm in Ohio, McClure attended Ohio State University with

the intention of returning to the family farm. Upon graduation in 1919, he unexpectedly received an offer to become an instructor in horticulture at Lingnan Uni-

versity in Canton, China. A youth in search of adventure, he accepted the offer and, except for two

furloughs, remained in China until 1932. During that time, he

became fluent in Cantonese and led numerous plant exploration trips, in part for the USDA. McClure was made curator of the herbarium at Lingnan, and he initiated a bamboo garden there. In 1936, after earning his doctoral degree, McClure returned to China, where

he remained until 1941, when the war forced his return. Subsequently, he visited nearly every Latin American

country,

researching and collecting bamboo.

Clure probably saw and studied more species of bamboo

Mc-

in their native habitats

than anyone before or since. During his time in China, McClure shipped hundreds of plants to the United States and was directly responsible for the introduction of 56 new species and cultivars of bamboo, more than any other plant explorer. In the U.S., McClure was actively involved in researching commercial bamboo applica-

tions. Many decades later, McClure’s research and writings still form a sound basis and foundation for bamboo inquiry. For a plant that is still relatively unknown, and about which much of what is “known’ is still in flux, and much new has been discovered, the continuing importance and validity of McClure’s research and writings

speak eloquently of the substance of McClure and his work.

McClure’s successor, Thomas R. Soderstrom, conducted extensive research on New World bamboos. His efforts, and those of his colleagues, especially Cleo Calderén, helped to bring to light, classify, and define the more than

120 species

of herbaceous, neotropical bamboos and bamboo allies. More recent carriers of the torch include Emmet J. Judziewicz, with his extensive research and writings on New World bamboos and grasses, Margaret J. Stern for her work on bamboo

ecology, and Lynn

G. Clark. The studies conducted by

Clark and her colleagues have been landmarks in bamboo research, uncovering the origins of bamboos and, in the process, redefining both bamboos and the basal

grasses. Clark’s extensive research and writings on New World bamboos have helped fill a once-great gap in bamboo literature. Of particular interest to the bamboo gardener are Clark’s contributions to our understanding of Chusquea. Clark is

213

214

Chapter 7

currently the leading authority on Chusquea, the world’s largest and most diverse bamboo genus. These leading researchers have largely focused on the bamboos of the New World, a relatively overlooked but important area of study. In their study of New World bamboos, they join their colleagues

from other parts of the Americas, includ-

ing Ximena Londono in Columbia, the current authority on Guadua, Gilberto Cortés in Mexico, Tatiana Sendulsky in Brazil, and Fernando Zuloaga from Argentina.

End of an Era From 1898 to 1975, through the efforts of its plant explorers and researchers, the U.S. Department of Agriculture introduced hundreds of different bamboos from around the world, under the assumption and hope that bamboo would become a widely planted and commercially viable crop in the United States. The expectation was never realized. The efforts of the USDA, dedicated researchers, and other pro-

ponents of bamboo were brought to an abrupt close in the 1960s, just as the viability of large-scale commercial production was about to be tested.

Two important experiments were initiated with the active cooperation of the New Crops Branch of the USDA around

1960. The first, a study of Phyllostachys

bambusoides and the loblolly pine (Pinus taeda) to compare yields for pulp produc-

tion, was launched in 1959, and the following year some 100 acres (40 hectares) of five Phyllostachys species were planted at Auburn University’s main Agricultural

Experiment Station in Alabama in order to study the problems of production, harvesting, and utilization.

On July 1, 1965, the United States Department of Agriculture discontinued cooperation in these programs, ostensibly as an economy measure. As a result, harvest research was drastically curtailed, and utilization research was abandoned. It

is speculated that large commercial interests with extensive holdings of loblolly pine were a force in the cessation of research efforts. At about the time that largescale

research

on

bamboo

ceased,

the

Southeast

began

intensively

cropping

loblolly pine for pulp production. Bamboo

research was killed just as preliminary results of the experiments

were becoming known. The cessation of virtually all support and funding halted

further as: sssments. Still, the preliminary results were compelling to anyone with a mind not tainted by competing economic interests. (See the preceding chapter for a further discussion of the comparison study of bamboo and loblolly pine.)

Bamboo in America

Overcoming an Archaic Law In 1918, under the authority of law enacted by Congress on August 20, 1912, the Secretary of Agriculture issued a directive that prohibited the importation of bamboo seeds, plants, or cuttings capable of propagation. The object of the order was to prevent the introduction and spread of bamboo smut

(Ustiliago shiraiana) and

“other dangerous plant diseases.” At the time of the quarantine, the United States was embroiled in World War I, and there was a critical dependence on the cereal crops of the Midwest. Grain smuts were seen as a considerable threat, and there was concern that bamboo smut and other bamboo diseases could affect the cereal crops. At least one search of USDA

archives indicates that the threat may have

been more hypothetical than real, however, and that there may never have been a substantive basis for the quarantine

(Cooper

1995).

Neither bamboo

smut

nor

any of the other “dangerous diseases” have posed a threat or problem, yet the ruling remains. It has been suggested that the same

business interests that were a factor in

the Department of Agriculture’s cessation of bamboo research in the 1960s also helped keep the quarantine

regulation in force. These two developments

had a

major and lasting impact on bamboo in the United States. Through the decades, the USDA staff had included some of the world’s greatest and most committed bamboo researchers, explorers, and proponents, and the cessation of large-scale bamboo research by the USDA in 1965 brought an end to a significant and active contributor to the field. The subsequent cessation of new USDA bamboo introductions in 1975 seemed to spike the final blow. The elimination of this important force in new bamboo introductions, combined with an archaic law and a regulation derived from it, threatened to thwart any and all future introductions of “for-

eign” bamboo seeds and plants. The future of bamboo in America appeared bleak. Richard Haubrich, founding president of the American Bamboo

Society, suc-

ceeded in obtaining a limited permit to import bamboo under an exception that allows importation for “experimental or scientific purposes by the Department of Agriculture.” Under this provision, up to six plants of a given type can be brought into a USDA-approved quarantine facility. As of this writing, there are no more than half a dozen permit holders and quarantine facilities in the United States. Because of their rarity and limited number, the first plants released for sale typically bring exceptionally high prices, which progressively drop to normal levels as

propagation stocks increase and the bamboos become more readily available.

215

216

Chapter7

The American Bamboo Society For anyone interested in bamboo, membership in the American Bamboo Society

(ABS) is essential. The society embraces a broad range of interests and is inclusive of all that is related to bamboo.

Far more than most societies devoted to a single

plant type, the American Bamboo

Society has played a critical role in the preser-

vation and resurgence of bamboo in America.

Interest in bamboo as a premier landscaping plant is dovetailing with a renewed awareness of bamboo as an important source of food and fiber. In part because of the dedication of the American Bamboo Society’s founders and members, bamboo

may yet fulfill and exceed the promise of a century ago, when

American plant explorers were captivated by a plant whose exceptional beauty was only equaled

by its utility, and

who

dedicated

themselves

to bringing

its

bounty to America.

The cessation of large-scale bamboo research in 1965 and the cessation of new plant introductions by the Department of Agriculture in 1975 marked the end of an exciting era for bamboo American

Bamboo

proponents and enthusiasts.

Society was formed on October 20,

Filling this void, the

1979, in Encinitas, Cali-

fornia. Founding president Richard Haubrich had become intrigued by the beauty of the bamboo in the garden of the house he was renting. He watered and fertilized the bamboo to encourage its growth. The bamboo, Phyllostachys aurea, predictably spread into his lawn. Later, at a home of his own, he began growing a variety of bamboos.

Kenneth

Brennecke,

a colleague of Haubrich’s, also liked bamboo.

Both of them

knew Gilbert Voss, who was then the curator at Quail Botanical Gar-

dens in Encinitas. In 1979, while riding in a car together to attend a meeting at Huntington Gardens, they decided to establish an organization dedicated to bam-

boo. That October, the American Bamboo Society was formed, consisting of all of seven members. In February of 1980, Haubrich traveled to the former USDA

introduction sta-

tion near Savannah, Georgia, to obtain bamboo plants. While there, he also obtained a special permit to import bamboos “for experimental or scientific purposes” and made arrangements at Quail Botanical Gardens

for the necessary

quarantine facilities. Haubrich arranged for plants to be sent from Europe and Asia. He and society member Bill Teague made a collecting trip to Costa Rica, and Voss went to Mexico. Gib Cooper obtained Phyllostachys heterocycla {. pubescens seeds through a partner in China, and arrangements were made with Quail Botanical

Bamboo

Gardens to sell the seedlings to help finance the quarantine greenhouse. In subsequent years, other members made collecting trips to South America and China.

Gerald Bol dedicated extensive time and effort to bring back many New World Chusquea bamboos, his name becoming virtually synonymous with their American horticultural introduction. An article in the Los Angeles Times generated a growth spurt to 50 members. Critical mass achieved, the ABS continued to grow. The Northern California Chapter was formed in 1982, the Pacific Northwest the Northeast

Chapter

in 1989,

the Southern

and Caribbean

Chapters in 1983,

California Chapter

in 1989, the

Southeast Chapter in 1990, the Texas Chapter in 1992, and so on. New chapters

continue to form, and the American Bamboo Society’s individual chapters now cover most of the United States and beyond, from Puerto Rico and Florida, to New England, to the Southwest, to Alaska, and to Hawaii. Among its stated objectives, the American

Bamboo Society provides a source

of information on bamboo identification, propagation, and utilization; stores and disseminates this information through a journal and other publications; preserves existing bamboo

species;

and

increases

the number

of bamboo

species in the

United States by maintaining quarantine facilities for importation of bamboos from foreign sources. Although still relatively modest aged by volunteers,

in size, and run and man-

including its board of directors and officers, the American

Bamboo Society has grown tremendously since its inception. Continuing to fulfill its original objectives, the society imports new bamboos through several quarantine greenhouses; reprints out-of-print bamboo books; publishes a newsletter, journal, species and source list, and an Internet web site; and funds bamboo

re-

search and publications.

Sales of plants and other bamboo-related items are a major source of funding for the ABS. At periodic sales, the American Bamboo Society and its regional chapters offer a wide selection of reasonably priced bamboos, expensive rare bamboos,

anda

variety of bamboo items. The annual auction, conducted at the society’s na-

tional meeting, is one of the ABS’s largest fundraising events. The annual meeting rotates around the country among hosting chapters, offering a broader opportunity for society members and interested public to attend.

Publications The American

Bamboo

Society publishes Bamboo: The Magazine of the American

Bamboo Society, The Journal of the American Bamboo Society, and the American Bamboo

in America

217

218

Chapter 7

Society Bamboo Species Source List. All are free to society members, and all are excel-

lent sources of information. During his long tenure as editor of the American Bamboo Society Newsletter, Michael Bartholomew played a pivotal role in expanding the newsletter into a highly informative, bimonthly publication containing technical information, news of events, and information on new publications, conferences,

meetings, and all manner of topics related to bamboo. For the first two decades of the society’s existence, founding member and author of the society’s bylaws, Kenneth Brennecke, edited The Journal of the American Bamboo Society, an excellent reference source for both practical and technical research articles on bamboo.

ard

Haubrich,

the

founding

president,

compiled

and

produced

American Bamboo Society Bamboo Species Source List for 16 years, from

the 1981

Rich-

annual through

1996, creating a standard format for comparatively listing bamboos. The role of editor was subsequently passed to former-president George Shor. The source list is a comprehensive

listing of all bamboos

in cultivation in the United States. It in-

cludes a concise description of the bamboos, and the addresses, phone numbers, and requirements of the nurseries that offer the plants for sale. The source list also

includes chapter addresses, common bamboo synonyms, and sources for a variety of bamboo products, including books, crafts, fences, hardwood flooring, musical instruments, poles, and rhizome barriers. These publications, and membership in the American Bamboo Society, are essentials for anyone interested in bamboo. The American

Bamboo

Society’s web site (http://www.bamboo.org/abs/), de-

veloped and maintained by Barry and Peter Abrahamsen, is available to anyone with an Internet connection and is a rich source of bamboo information, as well as links to other bamboo web sites.

Membership As of this writing, joint membership in the American Bamboo Society and one of its regional chapters is $35.00 per year. You can apply for membership through a regional chapter or through the society’s national address: American Bamboo

Society

750 Krumkill Road Albany, NY 12203

Additional information, regional chapter contacts, and the most current mem-

bership requirements can be obtained from the American Bamboo Society’s web site, at http://www.bamboo.org/abs.

Bamboo in America

Related organizations Although most bamboo organizations throughout the world operate with minimal funding and no paid staff, the sense of community and common purpose is strong. The Internet, through web sites and e-mail discussion groups, has fostered an even greater level of sharing and communication. The societies with Western cultural

roots, including the American Bamboo umbrella organization composed Bamboo

Society, European Bamboo

of bamboo

societies throughout

Society (an Europe), and

Society of Australia, all have a natural affinity in that they are made up

by bamboo enthusiasts and advocates from countries and cultures without strong historical ties to bamboo. To a large degree, these societies share a common focus and mission, spreading knowledge, understanding, and acceptance of this remarkable plant, exploring its role in the modern economy and culture, and fostering a bamboo culture where there had been none. The societies from countries

with existing bamboo cultures tend to have a slightly different focus, more directed at the immediate and future economic implications of bamboo

for their

peoples, but the purposes of all the bamboo societies and organizations dovetail quite well, forming a loose but cohesive global community.

The idea for some sort of formal international bamboo association emerged from discussions during the Second International Bamboo Congress, in Prafrance, Anduze, France, in 1988. In 1992, M. Watanabe of Japan, Karl Bareis of the United States, Dr. Adkoli of India, and Yves Crouzet of the European Bamboo Society pre-

pared a working document for an international association of bamboo societies. The association began to take formal shape later that same year at the Third International Bamboo Congress in Minamata, Japan. By mid-1993, the International Bamboo Association (IBA) had formally emerged, building on earlier cooperative efforts. By the time of the Fourth International Bamboo Congress, in 1995 in Bali, the world gathering drew nearly 3000 participants. The International Bamboo Association is composed of member organizations from around the world. Focus varies among the participating groups, but the furtherance of bamboo binds the groups together. The American Bamboo Society is one of the member organizations. Others include such diverse groups as the Forest Research Institute of Bangladesh, various European bamboo societies, the India

Bamboo Society, China’s Bamboo Information Center and Nanjing Forestry University, the Japan Bamboo Society, the Zaire Bamboo Workshop, and others. Other international bamboo organizations include the International Network

for Bamboo and Rattan (INBAR), an intergovernmental organization established

ZL

220

Chapter 7

by treaty in November 1997, dedicated to improving social, economic, and environmental conditions through bamboo and rattan. Previously headquartered in India and now with primary headquarters in China, INBAR connects a global network of participants from the government, private, and nonprofit sectors in more than 50 countries. Its stated mission is to define and implement a global agenda for sustainable development through bamboo and rattan. Because addresses change with some frequency for these largely volunteer organizations, the Internet is the best source for current information on them. Most bamboo web sites contain links to others, so once started on one web site, you can readily explore the rest. The American

Bamboo

good beginning point. Failing that, the numerous

Society’s web site is a

Internet search engines will

quickly ferret out the various bamboo web sites and bamboo resources.

The Future There has been a resurgent interest in incorporating bamboo in landscape design. As with most plants, interest waxes and wanes as plants go in and out of style. The resurgent interest in bamboo in the United States, however, has emerged in conjunction with a broad base of committed and knowledgeable

laypeople with an

understanding of bamboo’s great utility, as well as its great beauty and its profound cultural importance for many of the world’s peoples throughout the history

of humankind. It was the hope and vision of David Fairchild, Barbour Lathrop, Frank Meyer, Robert Young,

E. A. Mcllhenny,

Floyd McClure, and other Ameri-

can bamboo pioneers that the utility and beauty of bamboo would be recognized

in this country. All these pioneers were dedicated to the belief that bamboo could and should be a widely planted commercial crop in the United States. This com-

mercial-agricultural connection was seen as the gateway for the development of a genuine bamboo culture in America. Although gardening and landscaping will help bring bamboo’s beauty and enchantment to the U.S. and other parts of the world where bamboo

is not a prominent

native plant, the emergence

of an en-

during bamboo culture most likely will still be partially dependent on an agricultural connection—food and fiber, to nourish and sustain, in both a physical and cultural sense. Through the efforts of the bamboo pioneers, by the 1960s, bamboo came very close to establishing a commercial-agricultural connection in the southeastern United States. Because it did not then achieve the goal, and because governmen-

tal funding was all but eliminated, bamboo in America was threatened with a re-

Bamboo in America

turn to the Dark Ages—a

fate from

which

it was rescued, thanks largely to the

founders of American Bamboo Society. Primarily through the initiatives and projects of ABS members, a renewed effort to reestablish the commercial-agricultural connections began in the 1990s. An example of one such effort is the series of Pacific Northwest Forestry Workshops, initiated by Gib Cooper,

Bamboo Agro-

a bamboo nurseryman and long-

time member of the American Bamboo Society. The decline in the Pacific Northwest’s timber industry

helped

approaches that are applicable

create a receptive not only within

environment

for alternative

the region, but throughout

the

world. Workshop participants have come from throughout the United States, Canada, Europe,

South America, the Caribbean, China, and other Asia-Pacific coun-

tries. Although any major results from the conferences are likely to be a long time

in coming, the conferences offer the prospect of the adoption of bamboo by largescale, conventional, mainstream business interests and cultures, as well as the fostering of smaller scale, non-conventional

agricultural interests, under the aus-

pices and legitimizing umbrellas of university extension services and chambers of commerce.

This workshop

model is now being extended to other regions of the

United States. The bamboo center of the United States began in the Southeast, with the indigenous presence of the country’s only native bamboo species, Arundinaria gigantea. For about

three-quarters of a century, spurred by the USDA’s active plant-

introduction and research efforts, the active bamboo Southeast.

Other historical centers emerged

center remained

in the

in Hawaii and on the West Coast,

often in association with Asian immigrants who brought with them an appreciation and understanding of bamboo culture. With the cessation of USDA

involvement and support, the center of bamboo

activity shifted to California and the West Coast, which offered both an excellent range of climates suitable to bamboo, and an ardent group of supporters who founded the American Bamboo Society. In the ensuing years, the American Bamboo Society helped fan the fires of interest and provided a geographically diverse center for bamboo, as new chapters were established throughout the United

States. Bamboo is now grown in the Northeast and Northwest, the Southeast and Southwest, the Midwest, and all along the West Coast from the Mexican border to

the Canadian border and beyond, including Hawaii and Alaska. Although the focus differs—from the hardy bamboos in the Northeast to the tropical species in southern Florida and Hawaii—the interest in bamboo is no less ardent. Today, perhaps as it should be, America’s bamboo center is everywhere.

22)

GHAR a

EAReS

Taxonomy

ESTIMATES VARY, BUT AT LEAST 90 genera and 1200 species of bamboos exist worldwide (Judziewicz et al. 1999). At various times, bamboos have been classified

as a separate plant family, Bambusaceae, as a subfamily, Bambusoideae, or as a tribe, Bambuseae (McClure 1966). Taxonomists now generally agree that bamboo is properly classified as Bambusoideae, a subfamily of the grass family, Poaceae. Controversy continues, however, regarding the major taxonomic divisions within

the subfamily. Various systems cluster tribes, supertribes, subtribes, and genera differently. Bamboos are the only woody grasses, but the existence of herbaceous as well as woody bamboos has further complicated classification. It is now gener-

ally accepted, however, that bamboos, the subfamily Bambusoideae, consist of two tribes: the tribe of herbaceous bamboos, Olyreae, and the tribe of woody bamboos, Bambuseae.

A significant portion of bamboo nomenclature can only be regarded as provisional. It is not uncommon

for a bamboo to come into flower, only to be reclassi-

fied and renamed. The analysis of cryptic characteristics of leaf anatomy and biochemical methodologies have given rise to taxonomic realignments. Within the

last 20 years or so, refined molecular techniques have been a revelatory new tool. In conjunction with other morphological information, molecular techniques have helped researchers uncover the evolutionary origins of grasses, resolve taxonomic inconsistencies, and more accurately assign taxonomic membership. The flower-

ing of an infrequently flowering bamboo, new taxonomic methodologies, and re-

222

Taxonomy

vised thinking among taxonomists can give rise to proposals for new genera or membership in a different tribe or subfamily—or a return to a prior grouping. Although

complex

taxonomic

issues are as interesting to the dedicated re-

searcher as they are seemingly unstable, most of these issues need not greatly trouble the average gardener, grower, or landscaper. With a few exceptions, notably the Himalayan mountain bamboos, species assignment is generally stable. Uncertainty and confusion have entered more often at the genus, subtribe, tribe, and subfamily levels—and at the other end of the naming scale, with the accepted

names for varieties, forms, and cultivars. Most of the apparent instability is manifest among closely related genera, as opinions vary on how inclusive or narrow the definition of a given genus

should be. For the most part, for practical purposes,

the confusion and disputes can generally be “resolved” by memorizing a few synonyms. One can look at bamboo taxonomy as having two missions. One mission is the delineation and definition of bamboo within the world of grasses, including all its groupings and subgroupings, in accord with natural evolutionary lines, including

genera and the member species and forms belonging to the genera. This mission is best addressed by research scientists armed with the tools of their trade, which

may include such methodologies as the analysis of lodicule morphology, photosynthetic pathway variations at the biochemical level, molecular markers in DNA

extracts, and so forth. A second mission of taxonomy may be regarded as one that meets the needs of the average gardener, grower, and landscaper, by providing a means for readily identifying bamboo in the field without resorting to cryptic characteristics or arcane methodologies. This mission addresses such questions as, “Is this the bamboo I want to dig, to plant, to buy, to sell, to harvest for shoots, to harvest for culms, to use to create a tall screen, and so forth?” and, “Is it a Semiarundinaria or Phyllostachys; a P. bambusoides or P. vivax?” and so on.

The average gardener, grower, or landscaper has a more basic taxonomic need that cannot be met by the more precise mechanisms of research taxonomy. Taxonomic classifications based on the characteristics of leaf anatomy, for example,

are “derived from the leaf blade as viewed in transverse section and from the abaxial epidermis,” and woody bamboos are characterized by “arm and fusoid cells, complex

vascular system of the midrib imbedded

in sclerome tissue, and verti-

cally oriented silica bodies” (Ellis 1986). Molecular DNA markers, the current taxonomic tools of choice, are even further removed

from lay application—clearly,

one is not likely to draw these sorts of distinctions during a walk through the gar-

223

224

Chapter 8 den or while identifying the bamboo

in a neighbor's grove. And

further, in the

words of C. M. A Stapleton (1997), in The Morphology of Woody Bamboos, “Even if technology provides a hand-held DNA extractor and sequencer and access to vast data

banks of known sequences for identification of plants, someone is still going to ask, ‘What do they look like?’”

The flowering parts of grasses have traditionally played a prominent role in bamboo

taxonomy.

Since most bamboos

flower with great infrequency, depen-

dence on the inflorescences for field identification is far from a viable option. Fortunately, among

the grasses, bamboos

have relatively distinctive vegetative fea-

tures, and field identification of bamboos is almost entirely dependent on these characteristics. Vegetative keys for field identification, while somewhat problematic, are nonetheless generally viable, working best in a geographic area or other venues where the range of species to be distinguished is limited and known. Overt characteristics are not sufficient to render taxonomic assignments, but

once the assignments have been made, vegetative keys are useful tools for field taxonomy.

In his book, The Bamboos, McClure

(1966) states the case, though

from

a different angle: While it is possible to recognize and identify individual species of bam-

boos, once they are thoroughly known, by an adequate array of vegetative characters, it is not always possible, given the present state of our

knowledge, to determine the generic affinities of an unknown bamboo with certainty, by means of vegetative structures alone. Once a bamboo is thoroughly known, its vegetative characteristics can provide a relatively reliable means of identification and an excellent field tool for the gardener, grower, and landscaper. The culm leaf is one of the most distinctive vegetative features, and it provides a ready method

for field identification—at least

during the bamboo’s shooting period. Culm leaves and branching patterns are two

prominent characteristics employed in field classification methodologies.

Evolution of Bamboo Taxonomy Since 1789, when the first bamboo genus was identified, approximately era and well more

than

1000 species names

have been assigned,

many

150 genlater to

fall from use because they were either illegitimate or synonymous with existing classifications. The first recorded attempts to rationally classify bamboo date to as early as China’s Jin Dynasty, around 317 to 420 a.p. The Bamboo Chart, compiled

Taxonomy

by Dai Kaizhi, identified 61 different bamboo types. Of the original 61 identified types, 34 remain today as distinctive species or varieties (Li 1997). In 1623, Caspar Bauhin used the name Arundo to describe reed grasses, and he further classified the plant that he called Arundo arboras a woody, treelike reed. He subsequently referred to a type of Arundo by the Indian term Bambus. His grouping included plants other than bamboo, but the classification had been narrowed,

and the root terminology, Arundo and Bambus, is carried forward, in modified form, to today’s taxonomy. Thomas R. Soderstrom summarized some of the history of bamboo taxonomy in his

1985

paper “Bamboo

Systematics:

Yesterday,

today, and tomorrow.”

In

1753, in the seminal work Species Plantarum, Linnaeus included all bamboos under

Arundo bambos. In the ensuing decades, it became clear that the grouping Arundo actually encompassed

many genera. In 1789, two botanists, Retzius in Sweden

and Schreber in Germany, decided that what had been called Arundo bambos was actually a distinct genus, Bambos, or in its Latin form, Bambusa. Identification of

new genera and species proceeded at a rapid rate. In 1815, the German botanist Kunth classified grasses into ten groups of genera, one of which was Gramina Bambusacea.

This scheme

was a precursor to the system of subfamilies in use

today and to the bamboo subfamily of grasses, now known as Bambusoideae. In

1835, in his study of Brazilian bamboos, groups of bamboo:

Nees von Esenbeck recognized three

Bambuseae and Arundinariae, both encompassing woody

bamboos, and Streptochaeteae, which encompassed herbaceous bamboos. As early as 1835, then, researchers recognized the possibility, or necessity, of including herbaceous species in bamboo taxonomy. Since the time of Linnaeus in the mid-18th century, until relatively recently, the taxonomy of all angiosperms has been based primarily on reproductive struc-

tures. Traditionally, grass taxonomy has been based largely on the overt characteristics of the plant’s flowering parts. Extensive analysis of spikelet structure

evolved into a complex cataloging system for taxonomic assignment. For most grasses, dependence on the flowering parts of the plant for classification seemed to work well, but most bamboos flower very infrequently, sometimes for periods that may span more than a century. At least one bamboo, Bambusa vulgaris, has never had a recorded period of full inflorescence. The sometimes absence of fruit, even when flowering does finally occur, and the practical lack of rigorous, con-

trolled field observation under the infrequent flowering conditions made bamboo classification all the more problematic.

More than a century ago, it became apparent that dependence on the overt

225

226

Chapter 8

characteristics of inflorescence was problematic for all grasses, leading to artificial

groupings that did not reflect a common ancestry. Parallel or convergent evolution could and did lead to artificial groupings when plants from separate evolutionary lines grew to resemble one another, tempting classification groupings that did not reflect their dissimilar evolutionary origins. For example, the basis for placing bamboo

fleshy fruit was once

in the tribe Bacciferae, but fleshy fruit is an evolu-

tionary path taken more than once in widely separated evolutionary groups in both the New

World and Old World. The apparent

rhizomes from pachymorph

development

rhizomes is another common

of leptomorph

parallel development

among separate evolutionary lines.

In the 1930s, cell structure and other less obvious aspects of plant physiology were correlated with the structure of the flowering parts to resolve some of the problems with the earlier classification systems. Grass tribes could then be separated into broad natural groups. Yet, these elements were themselves subject to

some, though fewer, of the traps of parallel evolution, and they were sometimes self-contradictory, or too obtuse and indefinite to be practical. Until the late 1950s, most classification systems recognized two subfamilies of Poaceae: Panicoideae and Festucoideae. These systems reduced bamboo to tribal

status (Bambuseae) and included only woody plants in the tribe. With only two subfamilies, these systems were unable to account for several tribes that did not fit in either subfamily, and it became increasingly apparent that these systems were, at least in part, arbitrary and artificial.

In 1961, Lorenzo Parodi established a system of classifying the grasses of his native country. Under the grass subfamily Bambusoideae,

Parodi described four

tribes found in Argentina—all the woody bamboos in the tribe Bambuseae, and three tribes of herbaceous bamboos, Olyreae, Phareae, and Streptochaeteae. Although the great bamboo researcher F. A. McClure did not include herbaceous species in his writings on bamboo, Soderstrom (1985) cites discussions with McClure during the late 1960s and just prior to McClure’s death in 1971, where

McClure expressed his conclusion that the herbaceous species as well as the woody species should be included in the subfamily Bambusoideae. In 1959, during the IX International Botanical Congress in Montreal, Canada, the symposium

on the Natural Classification of the Gramineae emphasized the

synthesis of traditional morphological characteristics of the flowering parts of grasses with non-morphological, covert attributes. This approach gained increasing acceptance, and the analysis of leaf anatomy,

in particular, was employed

in

classifying bamboos and other grasses. The epidermis of ligules and the type and

Taxonomy

arrangement of cell tissues in the culm walls are examples of other cryptic features that were of value in tracing the evolution of bamboos and establishing their taxonomy

(Ellis 1986).

Leaf anatomy, in conjunction with other indices,

proved productive in delin-

eating evolutionary groups of grasses, in general, and bamboos, in particular. Stud-

ies of leaf anatomy have shown the similarity in basic structure among woody and herbaceous bamboos, as well as suggested distinctions at tribal and subtribal classification levels. Attempts to employ leaf anatomy to draw distinctions at the generic level were not particularly successful. Even at the subfamily and tribal level, inconsistencies remained, leaving the subfamily Bambusoideae, and thus “bamboo,” with uncertain membership, and the origins and evolution of bamboos and grasses fundamentally unresolved. The rightful inclusion of the herba-

ceous species in the Bambusoideae subfamily resolved some taxonomic issues, but many more remained.

Molecular Techniques and Cladistics Before the advent of cladistic analysis and the assistance of molecular techniques, which offer a greater array of discrete, identifiable characteristics, traditional methods of taxonomy

relied on differences among a relatively small number of char-

acteristics. Deciding which characteristics were taxonomically significant, and yielded the most meaningful distinctions, was a task fraught with pitfalls, with results that were inevitably incomplete and arbitrary. All such taxonomic systems, at least with plants as taxonomically difficult as bamboos, ultimately break down.

In some nebulous way, it has been hoped that if a plant is like another plant in certain ways then the plants should be grouped together and would bear some re-

lationship to their evolution and ancestry. But plants with very different lineages may evolve along parallel lines and have identical characteristics. Guadua, a South American bamboo once thought to be of the Bambusa genus of India and Asia, for example, is now known to be a distinct genus with a separate evolutionary path. The similarities between Guadua and Bambusa are the result of parallel evolution. Plants can be grouped together in a variety of ways for a variety of purposes. They can, for example,

be grouped by how they look, how they function, or by

their evolutionary relationships. In taxonomy, these grouping methods have often been muddled

together, and the methodology

has sometimes become

confused

with the purpose. A plant’s structure offers information that can help us to draw conclusions about a plant’s ancestry, evolution, and evolutionary relationships,

227

228

Chapter 8

and thus its taxonomy, but in and of itself, a plant’s structure is not, or should not be, the reason or basis for taxonomic assignment. Only within the last 20 years or so have the tools of molecular data and analysis been available to focus on the

purpose and separate it from the method. Fundamentally and authentically, taxonomy is not about a set of arbitrary similarities, but is a response to the questions,

What plants is this plant related to? What is its lineage? What are its ancestors? These are questions of evolution and evolutionary relationships. In cladistic analysis, plants are classified into groups according to “recency of

common descent,” basing the groupings on shared derived characteristics. Plants are grouped togetherif they share one or more characteristics that are derived from a common ancestor and are not present in any ancestral group. Given sufficient, informative data, this methodology can reconstruct evolutionary relationships and

give rise to an authentic and meaningful taxonomy. The problem with this approach lies in gathering accurate data on characteristics that are capable of revealing discrete differences and descent. Molecular data, particularly molecular data from DNA sequences, in conjunction with morphological data, help fill that need. Molecular techniques offer a large number of readily measurable characteristics. DNA sequences that change very little can reveal the evolutionary changes at the higher levels of taxonomy, such as subfamily and tribe. More rapidly changing sequences can show relationships between genera or species. DNA markers are in

every part of the plant and are not dependent upon a given state. Even dry leaves from herbarium collections can be used. Unfortunately,

molecular studies are not cheap;

their early stages of development;

the techniques are only in

and effective analysis is best accomplished

in

conjunction with other taxonomic tools and indicators. Nevertheless, molecular techniques and cladistic analysis have emerged as powerful taxonomic tools—so

powerful that these analytical tools are redefining their task and may one day call into question

the conceptual

tools (the binomial system and traditional taxon-

omy) they are meant to serve. Fundamentally, the purpose of taxonomic methodologies is not to classify all living entities into genera and species, but rather to understand the evolution and relationships of living things. As we learn more, the concepts of genera and species, and the binomial system itself, may one day prove to be artificial constructs

that need to be set aside (Stapleton

1997a) in favor of different conceptual con-

structs that do a better job of revealing the world and helping us grasp it. In the end, with respect to the adequacy of our analytical and conceptual tools, the world

itself is the final arbiter.

Taxonomy

Bamboo Redefined Early studies using molecular data were not very successful, leading to weak or er-

roneous conclusions. In these early studies, a limited sampling of woody bamboos and rice seemed to indicate, rather inconclusively, that bamboos were the oldest grasses and that rice might be a bamboo.

In a landmark study, published in 1995, Lynn G. Clark of lowa State University, and others, conducted a survey of virtually every tribe of grasses that had been included in the subfamily Bambusoideae (bamboos) in any classification system, as well as samples from all the major tribes of grasses. The study revealed that characteristics that had previously been associated with Bambusoideae were actually shared ancestral characteristics of the grass family. These characteristics

had been retained in bamboos, but they were not defining characteristics of Bambusoideae.

The

study

also

showed

that

some

(but

not

all)

of the

herbaceous

grasses, specifically Anomochloeae, Streptochaeteae, and Phareae, that had been classified as tribes of Bambusoideae could no longer be regarded as such and, thus, were not bamboos. In conjunction with fossil evidence, the study results suggested

that grasses likely evolved during the late Cretaceous period in Gondwanaland (Clark et al. 1995), some 65 million years ago, possibly coexisting with the dinosaurs. Bamboos (Bambusoideae) likely evolved later, probably in the Oligocene or Miocene epochs, some

30 to 40 million years ago (Lynn Clark, personal commu-

nication).

Although an exceptionally powerful tool, molecular techniques, even in conjunction with other analytical tools, have not yet resolved many of the larger issues of bamboo and grass taxonomy or of bamboo evolution. So far, molecular data support two major clades (evolutionary groupings) of woody bamboos (Bam-

buseae): “temperate” bamboos from both Asia and the New World, and “tropical” bamboos

from

both Asia and the New

World. The “tropical” clade includes

taxa that have adapted to the southern temperate zone and the equatorial highlands, including species of Chusquea, Aulonemia, and Neurolepis. Molecular data additionally support subdivision of the tropical woody bamboos into New World and Old World clades (Clark 1997a). To illustrate the implications, molecular data confirm that the Bambusa genus of the Old World tropics and the Guadua genus of

South America, although very similar, evolved separately. In contrast with the open habitats of their ancestors and most other grasses, the early bamboos, including both the woody tribe Bambuseae and the herbaceous tribe Olyreae, were adapted to forest environments. The once-held concept

229

230

Chapter 8

that bamboos are the most ancient grasses has proven untenable. In the words of Lynn G. Clark in her article “Bamboos: The centrepiece of the grass family” (1997a),

“the true bamboos

must

be seen as a more

recently evolved group of

grasses adapted to the forest habitat, and although they retain some ancestral features, particularly the inflorescences and flowers, true bamboos are anything but primitive grasses.”

Identification and Naming The taxonomy is relatively stable for most bamboo groups at the species level, but for many bamboos, genus assignment is tenuous, as are the accepted names and designations of variety, form, and cultivar. All of this is subject to ongoing inquiry,

debate, and revision. The estimated number of bamboo genera in the world has been variously placed at 49, by Clayton and Renvoize in 1986; 59, by Soderstrom and Ellis in 1986; 77, by Dransfield and Widjaja in 1995; and at least 90, by Judziewicz et al in 1999, Because bamboo is an under-studied and taxonomically difficult group, it is perhaps no surprise that succeeding studies and assessments un-

cover additional genera and species. Within the last decade, for example, new studies have revealed that 23 out of 56 species in Sumatra had not previously been described, and that

11 out of 42 species in Nepal and Bhutan

were newly

identified taxa. In her 1992 book, The Bamboos of Sabah, Soejatmi Dransfield points out that it is a mistake to generalize that bamboos are widely distributed, suggesting that only a few species are widely distributed in nature. For this reason, even studies that are focused on a relatively narrow geographical area are likely to miss bamboo

taxa. Many

even as some become

more

bamboos

are awaiting identification and description,

obliterated forever by the onslaught of irresponsible land

clearing and other ecological travesties. Classification of some genera,

for example

Phyllostachys, is quite stable. The

overt vegetative characteristics are distinct and uniform among its members, and

few other genera even approximate its appearance. It is relatively easy, even for the lay observer, to identify

a bamboo as a Phyllostachys. For other genera, such as

Arundinaria and Sasa and the genera that have been separated from them, the overt characteristics are less distinct and uniform, and their taxonomic assign-

ments are more provisional. Many Arundinaria, for example, differ considerably from other members of the genus, but the lines of natural groupings and the determination of which groupings legitimately require a separate genus is problematic, at least at the current stage of research.

Taxonomy New research has uncovered new genera and species and has given rise to the realignment or redesignation of the genera of some species. Following the litera-

ture over the course of more than a century, one may see a given species change its genus several times. And generic changes are not uncommon today, as new research continues to modify our understanding of bamboo. From the mid-1970s to mid-1980s, Chinese researchers defined four new genera and more than 250 new

species and forms. It should be noted, however,

that Chinese researchers, as re-

searchers everywhere, do not subscribe to a single point of view, and they differ on

various taxonomic issues, including the appropriateness of some of the new species and generic designations.

New genera are often created as breakouts of existing genera. For example, from Sasa come Sasaella and Sasamorpha; from Chimonobambusa

comes Qiongzhuea;

and from Arundinaria come Bashania, Pleioblastus, and Pseudosasa. Controversy persists on how many of the new genera are legitimate. Soderstrom and Ellis (1986) included these and related bamboos

in the subtribe Arundinariinae,

a group of

bamboos that they regarded as taxonomically problematic. In their words, Arundi-

nariinae is “a complex subtribe in which the generic limits are far from adequately resolved, particularly in the type genus itself and obviously closely related genera such as Fargesia. Numerous genera have been described, but many seem to have been erected on minor and insignificant characters.” Sasaella and Sasamorpha will very likely be eliminated as distinct genera one day and placed, once again, with Sasa. Some genera, such as Phyllostachys, and the entire genera of some subtribes described by Soderstrom and Ellis, such as the subtribe Arthrostylidiinae, are far more stable. A stable and accurate assignment of bamboo genera is one of the current challenges in bamboo taxonomy. Again, in the words of Soderstrom and Ellis (1986), “In some subtribes, such as the Arthrostylidiinae, many of the genera are clear-cut, but in other subtribes, such as the Arundinariinae, they are not. A neat definition of all the genera of bamboos is still far off.” With cladistics, and the as-

sistance of the molecular tools that are now available,

a more authentic delin-

eation should emerge as research progresses. The inherent difficulties of bamboo taxonomy are further compounded by a system of taxonomy that is sometimes at odds with what we now know as a result of molecular analysis and other modern scientific techniques. The need to better ground our taxonomy on evolutionary relationships, and the far better understanding of these relationships that modern scientific methods afford, will inevitably bring about changes in taxonomy. In 1753, with the publication of Species Plantarum, Linnaeus promulgated the

221

232 = Chapter8

fundamental

unit of naming,

which remains in use to this day, a binomial name

consisting of the genus and the specific member of the genus. For example, the binomial Phyllostachys aurea consists of the genus, Phyllostachys, and a modifier that designates the specific member of the genus, aurea. The species name is the bino-

mial, Phyllostachys aurea. The naming of plants of wild origin is now under the sanction of the International Code of Botanical Nomenclature (ICBN). Identifying and naming additional variations within the species is permitted and can be employed as warranted. In descending order of significance are subspecies (abbrevi-

ated ssp.), variety (var.), and form (f.). Examples are Chusquea mimosa ssp. australis, Thamnocalamus spathiflorus var. crassinodus, and Pleioblastus chino {. elegantissimus, Combinations are possible. For example, a variety may have more than one form, and thus require further distinction. An example of such is Pleioblastus chino var. vaginatus {. variegatus. Plants of cultivated origin are under the sanction of the International Code of Nomenclature

for Cultivated Plants (ICNCP). Cultivars may

be propagated vegetatively or from seed. A cultivar may consist of plants that either are or are not genetically identical, but they must nonetheless have characteristics that distinguish

them

from

other cultivars

(Griffiths

1994). The

cultivar

designation follows the species name. In earlier literature, one may see a cultivar designated by the abbreviation

“cv.,” as in Phyllostachys aurea cv. Koi. However,

the 1995 International Code for Cultivated Plants specifies that a cultivar is indicated by using single quotation marks, as in Phyllostachys aurea ‘Koi’.

The two sanctioning groups have different but somewhat

overlapping re-

sponsibilities, and the lines of distinction are not always clear. Bamboos with new and distinctive features can arise either vegetatively or from cultivated and indigenous

plants. Certain

seedlings, in both

features, such as yellow culms with

green striping, may arise from cultivated plants and may then be perpetuated through cultivation, yet these features may also reoccur spontaneously and re-

peatedly in nature. Some bamboo plants have long been known

in cultivation,

and their origins in the wild, if such exist, are unknown. On the other hand, some

cultivated bamboos rapidly become feral and are found in the wild. The origins are not always clear. Also, many

Malaysian

bamboos,

for example,

wild” may actually have been selected and propagated

that are “in the

over the course of thou-

sands of years by the ancient ancestors of modern-day Malaysians. The distinctions

between wild and cultivated plant forms become blurred. And further, because the criteria for nomenclature under ICBN are considerably more restrictive than those

for the ICNCP, some taxa are designated as cultivars even though they more properly should be treated as varieties or forms.

CUBAN IPE IE IR ©)

Bamboo Genera, Species, and Cultivars

SOME BAMBOO characteristics lend themselves to numeric summary or broadly grouped categorization. Among these are maximum height, maximum diameter, minimum chapter’s listing of bamboo species and varieties presents this summary information in a

but will only achieve maximum growth when cultural conditions are optimal. The numeric information offers a quick, relative comparison among species, but actual performance will depend on specific growing conditions. The characteristics of the species will also play a role in performance. For example, a bamboo that tol-

format similar to the American Bamboo Society

erates alkaline soils may demonstrate more vig-

temperature, and light requirements. This

Bamboo Species Source List. | wish to acknowledge the source list’s creator, Richard Haubrich, for creating designing, and for many years, maintaining what has become a standard format and reference for listing and describing bamboo for the gardener, grower, landscaper, and aficionado.

be more vigorous.

Descriptive Limitations

sources or different growing sites may differ greatly from previous information. For example, Chinese sources generally indicate a height of around 20 ft. (6 m) for Phyllostachys

The information cited for sunlight requirements, maximum height, maximum diameter, and minimum temperature is intended only as rough, relative guides, not as absolutes. Minimum

temperatures,

in particular, are subject

orous growth in a site with alkaline soil than a species that is intolerant of alkaline soil, even if the alkaline-intolerant species would otherwise

Height and diameter In some instances, information

from new

rubromarginata, yet it grows much

larger in

many parts of the United States. A harvested culm of P. rubromarginata growing near Bloomingdale, Georgia, measured 60 ft. (18 m) long

to wide variation and, in many cases, are

(Turtle 1995b). On the other hand, P. heterocy-

untested best estimates. Bamboo is a highly responsive plant. Many bamboos can adapt and survive in widely varied growing conditions,

cla f. pubescens may readily grow to 90 ft. (27 m) or more

in China,

with

a culm

diameter of

7 in. (18 cm) or more, but it is a difficult spe-

233.

234

Chapter 9: Bamboo Genera, Species, and Cultivars

cies to establish, and achieves its maximum potential only within a relatively narrow range of growing conditions. Under growing conditions that are far from the mark, P. heterocycla f. pubescens may not even achieve the more modest height expectations of some of the smaller species of the genus. It is also important to note that the figures cited for maximum height and diameter are only achievable with ideal climate, soil, nutrients, and moisture, in a large grove, clump, or forest that has been established for perhaps a decade or more. Although it is startling to see the impressive size that can quickly be achieved in a small garden plot, or even a container, such plants will nevertheless be considerably smaller than the cited maximums. Temperatures significantly colder or warmer than the ideal will also limit size. Many Phryllostachys bamboos, for example, grow much smaller in southern Florida or the northeastern United States than they do in either Georgia or

able to tolerate a brief frost for an evening or two, but not a full winter of that same temperature. In general, if continuing low tempera-

tures at or near the minimum are expected, choosing a more cold hardy bamboo may be warranted.

See chapter 3 for more information

on cold hardiness and on growing bamboo at temperatures colder than the normal minimum. Minimum temperatures are only approximations. Often, particularly with more recent introductions, insufficient data are available, and the cited minimums reflect only the best estimates of performance. The minimum temperatures cited are merely rough, relative estimates and are not intended to be definitive or absolute.

Sunlight In the descriptions that follow, sunlight requirements are listed as full shade, partial shade, mostly sunny, and full sun. The require-

Oregon. Phyllostachys makinoi, a species of Phyl-

ments are only an approximation.

lostachys that prefers more warmth,

boos will grow, if not necessarily flourish, in a wide range of light conditions. A bamboo’s light requirements and tolerances are partially determined by environmental conditions. For example, a Phyllostachys that generally thrives in full sun may need some sheltering in the nearly cloudless, arid American Southwest. A Fargesia that generally requires cool summers and partial shade may thrive in “full sun” in some of the cloudier parts of the coastal Pacific Northwest. Refer to the “Heat and Light” section of chapter 3 for additional examples and information.

will grow

much larger in Texas than it will in Washington state. Conversely, P. nigra, a species that

does well in cooler sites and prefers less intense sunlight, may grow larger in Washington than it would in Texas.

Minimum

temperature

Wind, humidity, sun, duration of low tempera-

tures, soil moisture, presence or absence of protective snow cover, and so on, all play a

role in determining whether or not a bamboo will be damaged by low temperatures. By convention, minimum

Most

bam-

temperatures cited in this

book refer to the point at which leaf damage begins to occur. The temperatures at which culm and rhizome death occur is generally far lower. The minimums cited assume short term rather than protracted exposure to the mini-

mum temperature. If cold temperatures are persistent rather than brief, the damage will be more severe. A semitropical bamboo may be

The Bamboos Because some botanical names change with relative frequency, any listing of bamboo species, varieties, forms, and cultivars is, of necessity, subject to ongoing revision. The species listing in this book is not intended as a definitive proclamation regarding naming conven-

Acidosasa

tions. Indeed, such matters are the proper domain of research botanists and taxonomists and are considerably beyond my own knowledge and abilities. In some instances, research

by accepted experts may offer a compelling basis for changing a long-established name. In other instances, expert opinion may vary

widely, and there may be little agreement on the correct name for a taxon. In some in-

stances, I have incorporated name changes when the information available to me seemed to warrant a change. In other instances, some long-standing names are clearly in need of revision, but the correct new name is unclear, and I have elected to continue with the existing naming convention, rather than further muddying the waters with new names that may not be appropriate. These are all judgment calls. Six months from now, or even a month from now, it is likely that | would make some of the judgment calls differently. The index of this book includes name crossreferences. The American Bamboo Society’s Bamboo Species Source List, updated yearly, is another source of information for alternate or new names.

If it is any concession to us, it is

the plant itself that has meaning. The names are only tools to refer to the thing itself. Perhaps, one day, our bamboo names will be better, more reliable tools. The situation is not too

Acidosasa

Native to China’s southeastern provinces, Aci-

dosasa consists of medium-sized,

arborescent

bamboos with leptomorph rhizome systems. The genus comprises some 22 spe: cies. The leaf sheaths are deciduous. Three to five principal branches are produced per node. The tessellated foliage leaves are generally large, suggesting sasa bamboos, hence the derivation of the latter part of the genus name. The other part of the genus name arises from the purported sour, or acid, nature of its shoots, many of which are regarded as choice and are pickled by local peoples.

Acidosasa edulis Maximum

height: 40 ft. (12 m)

Maximum

diameter:

Minimum

temperature:

2/4 in. (6 cm) 15°F

(-9°C)

Light: full sun Native to China’s Fujian and Jiangxi Proyinces, and cultivated in Zhejiang Province, Aci-

dosasa edulis is regarded as an excellent species for commercial

shoot production for late spring

and early summer shoots. The shoots are regarded as choice.

Acidosasa gigantea Common

synonym: Sinobambusa gigantea

Maximum

height: 55 ft. (17 m)

onerous, however. For the most part, we can

Maximum

diameter: 4 in. (10 cm)

readily make our way among the muddle by simply learning a few synonyms. While the unusual and exotic have considerable appeal for the collector, even the most common bamboos have much to offer the gardener, grower, and landscaper—as well as the collector. Often, the intrinsic beauty or usefulness of certain bamboos caused them to become popular in the first place, and thus more common—but only in number, not character. Although some of the plants listed here may be rare or difficult to find, all are currently cul-

Minimum

temperature:

tivated in the United States.

estimated

15°F (-9°C)

estimated

Light: full sun An attractive ornamental, this species also

has straight culms that are useful as bamboo timber. Introduced into Europe in the mid1990s, it is native to Zhejiang, Fujian, and Guangxi in China.

Ampelocalamus

This genus consists of subtropical and temperate bamboos with pachymorph rhizomes. Some species reach a height of 40 ft. (12 m). The branches are distinctively arranged in vertical groups that curve outward from the culm.

235

236

Chapter 9: Bamboo Genera, Species, and Cultivars

The upper portions of the culms are heavily pendulous, nodding deeply. Ampelocalamus species are semi-scandent bamboos. In the Himalayas, this genus is generally found in wetter subtropical forests than Himalayacalamus and Drepanostachyum. Ampelocalamus bamboos are tender to somewhat frost hardy. Ampelocalamus is native to China, India, Burma

(Myanmar), Nepal, and Vietnam. There are 11 known

species.

Ampelocalamus scandens Maximum

height:

34 ft. (10 m)

Maximum

diameter:

Minimum

temperature:

73 in. (0.8 cm)

32°F (0°C) estimated

Light: mostly sunny Ampelocalamus scandens can be found growing in steep rocks at elevations up to approximately

1000 ft. (300 m) in China’s Guizhou

Province.

to North America, and is North America’s only

native species. As currently constituted, Arundinaria comprises shrublike or treelike bamboos with three to numerous principal branches and leptomorph rhizomes. Arundinaria species are generally hardy, but typically less cold tolerant than Phyllostachys, although the hardier of the A. gigantea clones may equal or better any Phyllostachys in cold tolerance. Although usually smaller than those of Phyllostachys, the rhizomes of some Arundinaria species run more deeply and are more brittle, making management of lateral spread more difficult, The leaves at the tip of a new shoot are closely arrayed in a fanlike cluster. In some species, the culm leaves are deciduous, but in others, the culm leaves persist and may convey a less

Arundinaria

pristine, more unkempt look in the landscape.

In the 19th century, nearly all Asian temperate

and subalpine bamboos

Arundinaria, the placement may be regarded as provisional. Only A. gigantea, the type species for the genus, is secure. It is native only

(except Phyllostachys)

were heaped into the genus Arundinaria.

Arundinaria funghomii Maximum

height:

Today, Arundinaria remains something of a

Maximum

diameter:

catchall genus, even as classification efforts

Minimum

temperature:

define new genera within the group. Recogni-

Light: mostly sunny An attractive bamboo that may grow only 4

tion of the new genera and the proper demarcations for those genera is a matter of ongoing debate. In China and Japan, in the 20th century and particularly the 1980s, many new genera were separated out from Arundinaria and newly defined. The new genera were not always cogently defined, however, and not always widely accepted outside their country of origin—or even within their country of origin. Adding to the fracas, some ol the new genera were found to be identical to previously described genera, and therefore unnecessary. More recently, with increased sharing and availability of research information, more of the new genera from the Arundinaria heap are becoming increasingly accepted. For most bamboos assigned to the genus

30 ft. (9 m) 1/s in. (3 cm) 0°F (-18°C)

ft. (1.2 m) tall in cooler climates, Arundinaria

funghomii shoots in late spring or summer. The new culms are densely covered with a gray bloom, handsomely setting off the dark green foliage.

Arundinaria gigantea ssp. gigantea

Common names: cane, giant cane, river cane, canebrake bamboo Maximum

height: 33 ft. (10 m)

Maximum

diameter:

Minimum

temperature:

1?

in. (4 cm) —10°F

(—23°C)

Light: full sun Morphologically varied, and divided into two subspecies, Arundinaria gigantea is the only bamboo species native to the United States. Its

Arundinaria

natural habitat includes moist woodlands and areas along streams and backwaters, typically at elevations below 650 ft. (200 m). The predominant distribution of the two subspecies

grown in the same area lost all their leaves.

differs. Arundinaria gigantea ssp. gigantea is

The ‘Macon’ variant from northern Tennessee

more widely distributed in inland habitats and to the west; A. gigantea ssp. tecta is more com-

and central Kentucky has a strongly upright growth habit and is reportedly evergreen down

mon along the southeastern coastal plain

to —22°F

(Judziewicz et al. 1999).

Arundinaria

gigantea

ssp. macrosperma had previously been described as another subspecies, with characteristics that combine elements of A. gigantea ssp. gigantea and A. gigantea ssp. tecta, but it is not generally recognized as a valid name. At one time, thousands of acres of cane, the name given to Arundinaria

gigantea, spanned a

range from Maryland, Virginia, and Florida, across to Texas, north to Missouri, and up the Ohio River Valley. The cane meadows provided food sources for herds of migrating buffalo, as well as for cattle and other domesticated ani-

According to one report, after a winter low temperature of -4°F (-20°C), some forms exhibited little or no damage,

(-30°C)

(Turtle

while other forms

1995a).

In the 1788 book Flora Caroliniana, the “large cane” of the southern

United States was

termed Arundo gigantea. In 1803, Michaux elevated Arundo gigantea to the genus Arundinaria, thus separating it from the genus Bambusa, and

making the bamboo of the southern United States the first species of the genus to be described. It is the only New World member of the genus, and some authorities have sug-

mals. In some stands, the vegetation density

was remarkable, reaching up to 65,000 culms per acre (160,000 culms per hectare). The canebrakes offered a unique habitat for nesting birds and other wildlife. The decimation or demise of Bachman’s warbler, the passenger pigeon, and the Carolina parakeet has been attributed to the loss of the canebrakes (Bill-

ings and Houf 1995; Judziewicz et al. 1999). Although the species still extends over much of its former range, the acreage it covers is greatly diminished. Land clearing and overgrazing by livestock has decimated the oncegreat expanses of the native cane. It has been

suggested that hogs rooting and feeding on rhizomes were the principal cause of the rapid disappearance of cane in Missouri. Early settlers regarded canebrakes as indicators of fertile soil, and as a consequence, the canebrakes were subjected to intensive clearing for farm-

land. Arundinaria gigantea ssp. gigantea exhibits considerable variation, culm coloration and cold hardiness among the notable differences.

The gray bloom on a new Arundinaria funghomii culm.

238

Chapter 9: Bamboo Genera, Species, and Cultivars

gested that it is the sole legitimate member of the genus. Nearly all New World bamboos have pachymorph rhizome systems, and A gigantea is rare in the New World for its leptomorph rhizome system. A matter of speculation, Arundinaria gigantea may have migrated from Asia, across the Bering Bridge, during a time of ample warmth and moisture in the early to middle Miocene epoch, somewhere between 10 and 20 million years ago. If so, A. gigantea may be the only New World bamboo of Asian origin.

Arundinaria gigantea ssp. tecta Common

name: cane, switch cane

Maximum

height: 6 ft. (1.8 m)

Maximum

diameter:

Minimum

temperature:

2 in. (1.25 cm) —10°F

(—23°C)

Light: full sun This subspecies of

Arundinaria

gigantea has

at times been regarded as a separate species. Arundinaria gigantea ssp. tecta is a generally

smaller variant with persistent culm leaves and air canals in the rhizome system. Although neither subspecies is among the more attractive landscaping bamboos, A. gigantea ssp. tecta has a scruffier and less desirable appearance.

Both A. gigantea ssp. gigantea and A. gigantea ssp. fecta are polymorphic, exhibiting significant morphological differences. Although most bamboos will suffer leaf mortality and drop their leaves if conditions are too cold, then grow leaves again in the spring (if the branches and culms have not died), some variants of A. gigantea ssp. tecta are naturally deciduous in

their native habitats, routinely dropping their leaves each winter.

Bambusa A large genus comprising some

139 known

species, Bambusa is endemic to the semitropical and tropical regions of the Old World. Some of its species, notably B. vulgaris, have been distributed and cultivated for so long throughout the tropics, including the New World, that it is

often assumed that the genus is native to those areas as well. Most members of the genus are large timber bamboos. All have pachymorph rhizome systems. Some species have a very

tight caespitose growth habit, but others have longer rhizome necks and form open clumps with more widely dispersed culms. Bambusa has a multiple branching habit with a principal branch that is generally significantly larger than the others. In a few species, thorny spines

replace some of the branchlets. The culm leaf blades are erect and triangular. Culms are typically thick walled. Several species of Bambusa have considerably greater cold tolerance than species of other semitropical and tropical genera, and they can be successfully grown in temperate climates with mild winters, expanding the geographic reach of arborescent bamboo with a clumping habit—and giving the gardener, grower, and landscaper additional options. As the outer limits of cold tolerance are approached, however, the size and rate of growth is considerably reduced. In most American growing regions, shoot initiation naturally occurs in late summer to fall, presenting difficulties in marginal climates if the cold of winter arrives before the culms have finished shooting and hardening sufficiently, or before branching and leafing has been completed. As with other bamboo, if normal shooting and growth is disrupted, Bambusa will often initiate new shoots outside of its normal shooting interval. Because Bambusa does not require a period of cold dormancy, the plants can successfully be grown indoors as houseplants if light and humidity are sufficient. The smaller ornamental species of Bambusa are particularly suited to this purpose. The International Network for Bamboo and Rattan (INBAR),

in cooperation with the Inter-

national Plant Genetic Resources Institute,

developed a list of priority bamboos that they regarded as meriting focused research and wider use. Although the listing and choices are

240

Chapter

9: Bamboo

Genera,

Species, and Cultivars

somewhat controversial, it is nonetheless interesting to note that the original list of 19 species included 6 Bambusa: B. bambos, B. blumeana, B. polymorpha, B. textilis, B. tulda, and B. vulgaris. In suitable climates, many Bambusa also rank highly as garden and landscape ornamentals, providing attractive tall screens along perimeters and striking specimen plants in open areas.

Bambusa albostriata Common

synonym:

Bambusa textilis var. albos-

Maximum

diameter:

Minimum

temperature: 27°F (-3°C)

Maximum

height: 40 ft. (12 m)

Maximum diameter: 2 in. (5 cm) Minimum temperature: 32°F (0°C) estimated

Light: full sun This bamboo was originally classified as Bambusa textilis var. albostriata, but has been given its own

species ranking. Native to

China’s Guangdong

Province, it is differenti-

ated by attractive white striping on the lower culm internodes and culm leaves.

Bambusa arnhemica Maximum

height:

26 ft. (8 m)

Maximum

diameter:

Minimum

temperature:

4 in. (10 cm) 32°F

(0°C)

Light: full sun Indigenous to the moist tropical areas of Australia’s Northern Territory, this species is named for Arnhem Land, a region of northern Australia west of the Gulf of Carpentaria, and home of the country’s largest aboriginal reser-

vation. Bambusa arnhemica is found along water sources, becoming partially deciduous during dry periods. The species is polymorphic, sin different exhibiting different characteris areas. An attractive bamboo with thick culms, it is suited to only the warmest growing regions of the United States.

Bambusa bambos synonyms:

B. spinosa

Bambusa

arundinacea,

7 in. (18 cm)

Light: full sun Bambusa bambos is one of the most important bamboos in its native India. It is distributed throughout almost all of India and can be found at elevations up to nearly 4000 ft. (1200 m). In the Indian state of Maharashtra alone, B. bambos covers nearly 4900 square miles (12,750 sq. km)

triata

Common

Common names: giant thorny bamboo, Indian thorny bamboo Maximum height: 100 ft. (30 m)

(Tewari

1992). This very vig-

orous tropical species is a tender bamboo, and is suited to only a few areas in North America. It grows well at the Quail Botanical Gardens in southern California, and thrives in southern Florida, generally shooting in the fall, but delaying branching until the following spring. At the lower nodes, the branchlets are modified into sharp thorns, making an established clump nearly impenetrable by large animals. At the upper nodes, the branchlets become less thorny and more normally leaf bearing. The shoots are edible, but bitter, and require parboiling in at least two changes of water before they are ready for the table. Some sources regard them as excellent after parboiling. Because of its vigor and availability, Bambusa bambos has been used extensively in India for paper pulp production, but it is not the best quality for this purpose. Similarly, although its large, thick-walled culms are used in construction, the wood is less dense and lower quality than that of other bamboos.

Bambusa beecheyana Common Common

synonym: Sinocalamus beecheyanus name: Beechey bamboo

Maximum

height: 50 ft. (15 m)

Maximum

diameter:

Minimum

temperature:

5 in. (13 cm) 15°F

(—9°C)

Light: full sun Although fairly tolerant of cold, Bambusa beecheyana thrives and grows vigorously in

ra

o

4 a oO

c

g

rl

£

} a

P)

i

o

a

=

S

, o vu a g

2

& a

242

Chapter 9: Bamboo Genera, Species, and Cultivars

warm climates. New culms are covered by a white powder. The culms are elliptical in cross section and rapidly tapering. In southern China, B. beecheyana is a prime source of summer bamboo shoots. To prevent bitterness in the shoots, the soil is mounded around the base of the clump to keep the new shoots in darkness until they are dug. The clump forms a fountain of arching culms. It is an attractive ornamental, but requires space, particularly in warm climates, where it grows large quickly. It was named for Captain F. W. Beechey, when a naturalist on his ship collected the species in Macao, in 1827.

Bambusa dissimulator Maximum

height: 50 ft. (15 m)

Maximum

diameter:

Minimum

temperature:

22°F

(—6°C)

Light: full sun The branches of Bambusa dissimulator are somewhat thorny, but not as pronounced as those of other thorny species of Bambusa. The thick-walled culms are strong and can be used for scaffolding and other supports. The species is native to Guangdong

Province and Guangxi

in China.

Bambusa dissimulator var. albinodia Maximum

Bambusa blumeana

3 in. (7.5 cm)

height: 50 ft. (15 m)

Maximum

diameter:

temperature:

3 in. (7.5 cm)

Maximum

height: 82 ft. (25 m)

Minimum

Maximum

diameter:

Minimum

temperature: 28°F (—2°C)

Light: full sun Bambusa dissimulator var. albinodia is similar to the principal form, but the culm base nodes have white circular stripes. It is native to Guangdong Province and is cultivated in

8 in. (20 cm)

Light: full sun This native of India and Indonesia has branches with short, crooked thorns. Air roots

sometimes develop at the base of the nodes. Bambusa blumeana is used in a variety of ways, including

hedges,

windbreaks,

furniture,

farm

implements, baskets, and edible shoots. Reportedly, it is in such demand in the Philip-

22°F

(—6°C)

Hong Kong.

Bambusa dolichoclada ‘Stripe’ Maximum

height: 64 ft. (20 m)

Maximum

diameter: 4 in. (10 cm)

pines for furniture making that it is being im-

Minimum

temperature: 20°F (—7°C)

ported from Vietnam.

Light: full sun An attractive ornamental cultivated in Taiwan and southern Japan, Bambusa dolichoclada ‘Stripe’ has culms that are waxy yellow with dark green stripes.

Bambusa burmanica Maximum

height: 60 ft. (18 m)

Maximum

diameter:

Minimum

temperature:

4 in. (10 cm)

32°F (0°C)

Light: full sun

Indigenous to Burma and northern Thailand, Bambusa burmanica inhabits dry hillsides in evergreen and deciduous forests, and in open forests of pine and grasslands. It grows at elevations of up to 4300 ft. (1300 m). Used for

construction, fences, and weaving, the culms are strong and nearly solid. The large leaves may be up to 12 in. (30 cm) long and 2 in. (5 cm) wide.

Bambusa dolichomerithalla Common

name: blowpipe bamboo

Maximum

height: 35 ft. (11 m)

Maximum

diameter: 2 in. (5 cm)

Minimum

temperature:

15°F (—9°C)

Light: full sun Native to Taiwan and cultivated in Japan, Bambusa dolichomerithalla was introduced into America in 1980. Its common name, blowpipe bamboo, is derived from its long internodes and its traditional use as a blowpipe for cook-

ing. It is found along streams and waterways at

lower elevations.

Similar to the principal form, but the culms are dark green, with silver-white striping on

Bambusa dolichomerithalla ‘Green Stripestem’

35 ft. (11 m)

the internodes.

Bambusa eutuldoides

Maximum

height:

Maximum

height: 45 ft. (14 m)

Maximum

diameter: 2 in. (5 cm)

Maximum

diameter:

Minimum

temperature:

Minimum

temperature:

15°F

(—9°C)

Light: full sun Similar to the principal form, but the culms are yellow-green to orange-yellow, with dark green stripes on the internodes.

Bambusa dolichomerithalla ‘Silverstripe’ Maximum

height:

Maximum

diameter:

Minimum

temperature:

Light: full sun

35 ft. (11 m) 2 in. (5 cm) 15°F

(—9°C)

2 in. (5 cm)

22°F (—6°C)

Light: full sun This species is widely cultivated in southern China, where the thick-walled culms are used

in constructing farm buildings and farm implements. Unusually, the culm leaf auricles differ greatly in size. One of the pair is five times as large as the other.

Bambusa lako Common ‘Timor

synonyms:

Gigantochloa atroviolacea

Black’, Gigantochloa sp. ‘Timor Black’

Nv

Bambusa

Bambusa

dolichomerithalla ‘Silverstripe’. Quail Botanical Gardens.

Bambusa

Common name: Timor black Maximum height: 70 ft. (21 m) Maximum diameter: 4*in. (10 cm)

Bambusa longispiculata

Minimum

temperature: 25°F (—4°C)

Light: full sun A choice ornamental bamboo, Bambusa

lako was

known

‘Timor Black’. Its common

Maximum

height: 50 ft.

Maximum

diameter: 4 in.

Minimum

temperature:

(15 m). (10 cm)

28°F

(—2°C)

Light: full sun until recently

as Gigantochloa sp.

name derives from

its indigenous habitat on the island of Timor. The culms are initially green, turning brownblack to black with age, but retaining li ht green stripes. It is often mistaken for Gigantochloa atroviolacea, which it closely resembles. The culms of B. lako have a shiny surface, while those of G. atroviolacea have more of a matt finish. The shoots are edible.

In the early 1930s, Bambusa longispiculata was introduced

into Puerto Rico from India.

It now grows in many

New

World

regions. In

China, B. longispiculata is used on farms for building simple utilitarian constructions. Its appearance is similar

to that of B. tulda.

An at-

tractive ornamental, it forms open clumps and has the added bonus of good tasting shoots.

Bambusa malingensis Maximum

height: 35 ft. (11 m)

Maximum

diameter: 2

in. (6.3 cm)

Minimum

temperature: 20°F (—7°C)

Light: full sun A native of China’s Hainan

Island, the

strong culms of this species are used to make farm implements and frames for farmhouses. The lower branches may develop into soft or hard thorns. It forms tight erect clumps. At

Quail Botanical Gardens in southern California, it reportedly tolerates salty sea breezes without damage.

Bambusa membranacea Common

synonym:

Dendrocalamus

membra-

naceus

Maximum

height: 80 ft. (24 m)

Maximum

diameter: 4 in.

Minimum

temperature: 25°F (—4°C)

(10 cm)

Light: full sun Until the late 1990s, Bambusa membranacea was

classified as Dendrocalamus membranaceus

It is distributed in Burma,

India, Laos, Thai-

land, and China. The culms, slender for their height, grow in loose clumps.

Used for con-

struction and tools, B. membranacea reportedly is also considered a promising species for paper pulp. The young shoots are choice. Bambusa lako. Quail Botanical Gardens.

245

Bambusa membranacea.

Quail Botanical Gardens.

Bambusa

Bambusa multiplex

because its culms are relatively

Common

synonym:

the culm

Common

name: hedge’bamboo

Bambusa glaucescens

Maximum

height:

35 ft. (11

Maximum

diameter:

Minimum

temperature:

12

slender, and

walls rather thin, B. multiplex is not

one of the most desirable species for wood

or

pulp production. The shoots are not amenable

m)

in. (4 cm)

to the table, being quite bitter.

12°F (-—11°C)

does, however, excel as an attractive, clump-

Light: full sun

ing, hedge bamboo

This species

suited to a broad range of

pachymorph bamboos, Bambusa multiplex is widely cultivated throughout the world as a windbreak and privacy hedge. In China, it has

climate conditions, from the tropics to northern California and coastal climates even farther north. Indigenous to China, Bambusa multiplex is

been used in weaving and papermaking,

known

One of the hardiest of the semitropical

but

as Chinese bamboo

in India, where it

was introduced in 1794. The species has long been cultivated in many

areas, and a number

of distinctive ornamental

cultivars have devel-

oped over time. The species had already made its way to Europe prior to 1800, and a presumed variant,

B. nana, was referenced as early

as 1812. The culms of the principal type natu-

rally arch, forming a rather broad hedge, but they

take well to pruning and shaping, permit-

ting a reasonably

upright shape. Contributing

to its appeal as a hedge, the culms emerge in a tight clump, and bushy branches grow on the lower

nodes of the culms.

Bambusa multiplex ‘Alphonse Karr’ Common

name:

Alphonse

Karr

Maximum Maximum

height: 35 ft. diameter: 1

(11 m) in. (4 cm)

Minimum

temperature:

12°F (—11°C)

Light:

full sun

General characteristics of this cultivar are the same as Bambusa multiplex, but the culms

are yellow with irregular green striping. The new culms often have a reddish blush, particularly when

exposed to strong sunlight. ‘Al-

phonse Karr’ is a choice ornamental in the landscape, and an excellent container plant for the home.

It prefers full sun in the areas of

North America where it can be grown, yet in the tropics, it needs shade to reach its maximum

height—an

example of the relativity of

light requirements. Quail Botanical Gardens.

It is

very widely cultivated,

and additional variants have emerged,

includ-

247

248

Chapter 9: Bamboo Genera, Species, and Cultivars

ing some with light green culms and dark green stripes.

Bambusa multiplex ‘Fernleaf’ Common

name: fernleaf bamboo

Maximum

height: 20 ft. (6 m)

Maximum

diameter:

12 in. (1.25 cm)

Minimum temperature: 12°F (-11°C) Light: full sun An unstable cultivar, Bambusa multiplex ‘Fernleatf’ is characterized by small, tightly spaced, closely two-ranked leaves. Long distributed in the nursery trade, it generally keeps its notable characteristics in infertile, drier conditions when its height is kept to no more than 10 ft. (3 m) or so. When offered better soil and moisture, ‘Fernleaf’ tends to grow taller and

lose its fernlike characteristics. It has hollow culms, unlike the solid-culmed B. multiplex var. riviereorum, which it otherwise resembles.

Bambusa multiplex ‘Golden Goddess’

Common name: golden goddess bamboo Maximum height: 10 ft. (3 m) Maximum

diameter:

2 in. (1.25 cm)

Minimum

temperature:

12°F

(—11°C)

Light: full sun A cultivar perhaps developed in the San Diego area of southern California, ‘Golden Goddess’ is similar to Bambusa multiplex ‘Fernleat/ but the plant is smaller and the leaves are generally larger. The culms have a yellowish cast.

Bambusa multiplex ‘Goldstripe’ Maximum

height:

35 ft. (11

Maximum

diameter:

Minimum

temperature:

m)

2 in. (1.25 cm) 12°F

(-11°C)

Light: full sun Similar to the typical form, but the culms have a gold stripe that bleeds into the green.

Bambusa multiplex var. riviereorum Common name: Chinese goddess bamboo Maximum height: 6 ft. (1.8 m)

Maximum

diameter:

4 in. (0.6 cm)

Minimum

temperature:

12°F (-11°C)

Light: full sun Unlike the cultivar Bambusa multiplex ‘Fernleaf, which it generally resembles, B. multiplex var. riviereorum is a stable form, maintaining its low height and delicate fernlike foliage. Its solid culms are a way to distinguish it from a small B. multiplex ‘Fernleaf’ plant. In the landscape, a slight breeze readily animates its lacy foliage, and it is also an excellent houseplant, given sufficient sun.

Bambusa multiplex ‘Silverstripe’

Bambusa multiplex ‘Alphonse Karr’. Bamboo Sourcery.

Maximum

height: 45 ft. (14 m)

Maximum

diameter:

Minimum temperature: Light: full sun

12 in. (4 cm)

12°F (-11°C)

Bambusa multiplex ‘Stripestem Fernleaf’. Quail Botanical Gardens

250

Chapter 9: Bamboo Genera, Species, and

Cultivars

The most vigorous cultivar of the species, Bambusa multiplex ‘Silverstripe’ requires a warm climate and ample moisture to achieve its size potential, but like the other cultivars, it tolerates a wide range of conditions, from cool summers and winters to the conditions of a home interior. Many of the leaves are variegated with white striping. The culms also bear

Bambusa mutabilis Maximum

height: 23 ft. (7 m)

Maximum

diameter:

Minimum

temperature:

2 in. (5 cm) 22°F

(—6°C)

Bambusa multiplex ‘Stripestem

Light: full sun Native to China’s Hainan Island, Bambusa mutabilis is an attractive bamboo, somewhat resembling B. textilis in clump habit and leaf shape. The culms are thin walled. New culms have a light covering of waxy powder, and a ring of white waxy powder below the node.

Maximum

height: 20 ft. (6 m)

Bambusa nana

Maximum

diameter:

Maximum

height: 20 ft. (6 m)

Minimum

temperature:

Maximum

diameter:

Minimum

temperature:

occasional threadlike white striping.

Fernleaf’

2 in. (1.25 cm)

12°F (—11°C)

Light: full sun Similar to Bambusa multiplex ‘Fernleat’

except the culms are yellowish to reddish, striped with green.

2 in. (5 cm) 15°F

(—9°C)

Light: full sun Bambusa nana was referenced as early as 1812, as an herbarium

specimen from north-

Bambusa multiplex ‘Willowy’

eastern India. Commercially cultivated in Thailand, B. nana is an old synonym for B. multiplex. However, the B. nana of Thailand appears to be a different species than B. multiplex. Although its authentic identity may be in question, Bambusa nana is nevertheless a very worthy bamboo. An appealing ornamental, it forms a tight clump with erect culms that are devoid of leaves on the lower nodes. The culms arch outward near the top to complete an attractive silhouette. The straight culms are also very strong and are highly desirable for construction when smaller diameter culms are required.

Maximum

height: 20 ft. (6 m)

Bambusa nutans

Maximum

diameter:

Minimum

temperature:

Bambusa multiplex ‘Tiny Fern’ Common

name: tiny fern bamboo

Maximum

height: 3 ft. (1 m)

Maximum

diameter:

Minimum

temperature:

Ys

in. (0.3 cm) 12°F (-11°C)

Light: full sun This cultivar is a dwarl form of Bambusa

multiplex var. riviereorum. Its leaves are often less than 1 in. (2.5 cm) long. Small and delicate, ‘Tiny Fern’ is an excellent container plant.

Common

name: willowy hedge bamboo % in. (2 cm) 12°F (—-11°C)

Light: full sun The culms, branches, and twigs are exceptionally slender, and the leaves narrow. The culms have a very pronounced arching and drooping habit. Although ‘Willowy’ is not a new cultivar, its characteristics are not in much demand, and it is not widely distributed in the nursery trade.

Maximum

height: 40 ft. (12 m)

Maximum

diameter:

Minimum

temperature: 25°F (—4°C)

3 in. (7.5 cm)

Light: full sun

Widely cultivated in northwest India, Orissa, West Bengal, and Bangladesh, Bambusa nutans is an attractive ornamental, but also possesses good commercial attributes. The culm wood is straight and strong. It is one of the six species commonly used in the Indian paper industry.

Bambusa Bambusa

nutans is also cultivated commercially

in Thailand. In China, itis used for farm implements and building material

Bambusa oldhamii Common

synonym:

Sinocalamus oldhamit

Common

names: giant timber

Maximum

height:

Common

Maximum

diameter:

temperature:

Bambusa edulis

Maximum

height: 65 ft. (20 m)

Minimum

Maximum

diameter:

Light: full sun

Minimum

temperature:

3 in.

(7.5 cm) 20°F (-7°C)

known

bamboo, by the name

Bambusa edulis

B. odashimae is cultivated in the northern

of Taiwan. It either is native

part

to the island or,

more likely, was naturalized long ago.

65 ft.

(20 m)

4 in.

(10 cm) 20°F

(—7°C)

Bambusa oldhamii is an attractive timber

Light: full sun Widely

Old-

ham’s bamboo

Bambusa odashimae synonym:

bamboo,

The

and the most commonly

cal clumper

in America.

California and Florida, where it reaches a height of 55 ft.

(17 m).

In warmer

production,

tively cold hardy, its maximum

shoots.

for its

even taller. Although

it can

the plant is relasize is consider-

ably smaller as warmth decreases, reaching less

Ws

Bambusa nana. Quail Botanical Gardens.

areas, such

as Central America and its native China, grow

grown

tropi-

It thrives in southern

culms can be used for construction and paper but it is primarily

grown

Bambusa oldhamii. Quail Botanical Gardens.

251

2

oy)

Chapter 9: Bamboo Genera, Species, and Cultivars

than

10 ft. (3 m) tall at the cooler limits of its

growing range. In North America, it was once misidentified as Dendrocalamus latiflorus. This species has an erect habit, relatively short branches, and large, long leaves. Native to southern China, Bambusa oldhamii was

Maximum

diameter: 6 in. (15 cm)

Minimum

temperature:

27°F

(—3°C)

height: 45 ft. (14 m)

Light: full sun Bambusa polymorpha is one of India’s most important bamboo species. It is widely distributed in the Old World tropics, and among its growing regions are China, Thailand, Bangladesh, Burma, and Indonesia. Bambusa polymorpha excels in almost all respects. It is an attractive, graceful, ornamental, timber bamboo with superior wood quality. It is excellent for pulp and paper, building construction, and fiberboard. Some reports indicate that the shoots are distinctively sweet, even in the raw state. Other reports indicate that they are edible, but somewhat bitter. As with all semitropical and tropical bamboos, unless you truly know what you are doing, the shoots should first be parboiled as a precaution to purge any possible cyanogens—the volatile poisons are readily eliminated by parboiling. Although introduced into the United States in 1924, Bambusa polymorpha remains rela-

Maximum

diameter: 2 in. (5 cm)

tively rare in this country. In mature clumps,

Minimum

temperature:

the lower nodes are free of branches. The branches and twigs themselves are long and slender, and the leaves are among the more slender and delicate of the arborescent tropical bamboos. Its cold sensitivity, however, significantly restricts its domain.

introduced into Taiwan

long ago, where it is

now widely cultivated for its excellent tasting shoots. The culm wood is only marginally suitable for building construction, but it is attractive and is a good choice for furniture making. Bambusa oldhamii takes well to pruning and makes a spectacular, tall hedge. For the scale of many of today’s landscaping needs, however, other shorter and more compact

bamboos,

such as B. textilis, have been suggested as a substitute, but when space permits, and where strong, dry winds are nota threat to its large leaves, the towering presence of B. oldhamii is impressive in the landscape.

Bambusa oliveriana Maximum

32°F

(0°C)

Light: full sun Native to India and Burma, Bambusa oliveriana is named for J. W. Oliver, who collected it in flower in the 1890s. The culms are glossy green and thick walled. It reportedly has good tasting shoots.

Bambusa rigida

Bambusa pachinensis

Maximum

height: 40 ft. (12 m)

Maximum

height: 33 ft. (10 m)

Maximum

diameter:

Maximum

diameter:

Minimum

temperature:

Minimum

temperature:

2/2 in. (6.3 cm) 20°F

(—7°C)

Light: full sun This species is indigenous to Taiwan and the mainland Chinese province of Fujian. Bambusa pachinensis was once classified as a variant of B.

textilis. is commonly employed as a windbreak in its native environment.

Bambusa polymorpha Maximum

height: 80 ft. (24 m)

24

in. (6 cm) 32°F

(0°C) estimated

Light: full sun Bambusa rigida is indigenous to southern and southeast coastal China, where the culms are used variously for paper, tools, and construction of sheds and other utility buildings. The shoots are bitter and are not harvested for food.

Bambusa rutila Maximum

height: 40 ft. (12 m)

Maximum

diameter: 24 in, (6 cm)

Bambusa pachinensis.

Quail Botanical Gardens

Chapter 9: Bamboo Genera, Species,

Minimum

temperature:

and Cultivars

32°F (0°C) estimated

Light: full sun Distributed in Guangdong Province in China’s southern coastal region, and cultivated in Hong

Kong, Bambusa rutila is weakly thorny

on the lower culm nodes. The thick-walled culms are strong, but not straight, relegating them to utilitarian construction.

Bambusa sinospinosa Common

names: Chinese thorny bamboo,

spiny bamboo Maximum

height: 70 ft. (21

m)

Maximum

diameter:

Minimum

temperature: 20°F (—7°C)

5 in. (13 cm)

Light: full sun Bambusa sinospinosa is native to China.

nodding gracefully at their tips. The lower nodes are free of branches to a greater degree

than most of the genus, up to as much as three-quarters of the culm height in mature specimens, adding to its arborescent stature and ornamental appeal. The delicate foliage is ttractive, matching the gracefulness of the rest of the plant. Banzbusa textilis is justly regarded as an attractive ornamental. Bambusa oldhamii has long been a landscaping standard in America’s warmest regions, but for today’s landscaping needs, the shorter and more compact B. fextilis may be a better choice. Its smaller leaves are also less subject to damage from strong, drying winds.

Bambusa textilis var. gracilis

Many of its branchlets are hardened into

Common

thorny spines, making an effective barrier

Maximum

height: 26 ft. (8 m)

or natural fence. The thick-walled culms are

Maximum

diameter:

used to make rafts, water pipes, the buckets

Minimum

temperature:

of waterwheels, and other construction. The shoots are edible and often pickled.

Light: full sun This ornamental variety of Bambusa textilis has culms that are much more slender than the type form, and have nodding tops.

Bambusa textilis Common

name: weaver’s bamboo

Maximum

height: 40 ft.

Maximum

diameter: 2 in. (5 cm)

(12 m)

Minimum

temperature:

13°F

(—11°C)

Light: full sun Native to China, Bambusa textilis has long internodes and strong but pliable fiber, making this a choice bamboo for weaving all manner of materials, from delicate baskets to strong rope. The absence of branches and branch scars, and the absence of prominent culm nodes, contributes to its desirability as a source of weaving material. The thin-walled, but strong, whole culms are used in craftwork and some furniture making. Silicic acid, known as tabasheer, is collected from the internodes for use in Chinese medicines. Bambusa textilis is also resistant to the dreaded powder post beetle, a pest of great concern in tropical environments.

The culms grow strongly upright before

name: slender weaver’s bamboo 1/s in. (3 cm) 15°F (—9°C)

Bambusa tulda

Common names: Bengal bamboo, spineless Indian bamboo, Calcutta cane Maximum

height: 70 ft. (21 m)

Maximum

diameter: 4 in. (10 cm)

Minimum

temperature: 27°F (—3°C)

Light: full sun A tender, giant timber bamboo native to India, Bambusa tulda was introduced into the United States in 1907. Its areas of distribution include Bangladesh, Burma, Thailand, and China. The lower branches on large culms are leafless and nearly thornlike. The culms are thick walled, and the culm wood is dense and fairly strong. Although the fibers are only moderately long, this species is suitable for papermaking. The culms are used in heavy construction and scaffolding, as well as craftwork. In northern Thailand, B. tulda is report-

Bambusa

textilis. Quail Botanical Gardens.

Chapter 9: Bamboo Genera, Species, and Cultivars edly one of the two most important species for shoot production, although the shoots are said to be somewhat bitter. The culms are imported into the United Kingdom as “Calcutta cane” for the construction of split-bamboo fishing rods

name: punting pole bamboo

Maximum

height:

Maximum

diameter:

Minimum

temperature:

Light:

55 ft.

(17 m)

2'4 in. (6 cm)

15°F

(—9°C)

full sun

Similar

B. tuldoides is a native of

China’s Guangdong

culms, grow-

culms are used as punting poles to propel wa-

tercraft, hence its common

name, punting pole

The shoots are edible.

Shavings from

the culm cortex are used in Chinese medicines. The Portuguese first introduced B. tuldoides to the New World, in Brazil, around the 1840s.

Bambusa tuldoides ‘Ventricosa’ Common

in appearance to Bambusa tulda,

It produces numerous

ing in a tight clump. The culm wood is strong, and useful for weaving and building sheds and other utility constructions. Traditionally the

bamboo.

Bambusa tuldoides

Common

Province.

synonym:

Bambusa

ventricosa

Common name: Buddha’s belly bamboo Maximum height: 55 ft. (17 m) Maximum

diameter: 24

in. (6 cm)

Minimum

temperature:

15°F

(—9°C)

Light: full sun A native of southern

China,

doides ‘Ventricosa’ exhibits growth

habit when

Bambusa tul-

a conventional

planted in the ground and

given ample water and nutrients.

Although

uselul as a tall hedge in this context, it is most known for its appearance when potted, pruned, and stressed by withholding water. Under these conditions,

the plant readily be-

comes dwarfed and develops shortened, swollen internodes, hence its common name, Buddha’s belly bamboo. It is generally grown as an ornamental potted plant or as bonsai. The shoots reportedly taste excellent.

Long known

as B. ventricosa, this cultivar is now regarded by authorities as a selection of B. tuldoides

Bambusa tuldoides ‘Ventricosa Kimmei’ Maximum

height:

55 ft. (17 m)

Maximum

diameter:

Minimum

temperature:

2/4 in. (6 cm)

Light: full sun

15°F

(=926)

This cultivar is similar to Bambusa tuldoides ‘Ventricosa’, but the culms are yellow with a few green stripes, and the foliage leaf blades have a few white stripes

Bambusa vulgaris Common

new culm leaf sheaths are green with yellow

name: common

bamboo

striping.

Maximum

height: 70 ft.(21

m)

Maximum

diameter: 41 in. (11 cm)

Bambusa vulgaris ‘Wamin’

Minimum

temperature:

Maximum

height:

Maximum

diameter: 3 in. (7.5 cm)

Minimum

temperature:

27°F (—3°C)

Light: full sun An Old World bamboo,

Bambusa vulgaris

propagates easily and is one of the most widely distributed tropical bamboos in both the Old and New World. It was cultivated by Spanish colonists in southern

Florida in the

1840s, and

it may have been the first foreign species introduced into America. Bambusa vulgaris was also among the first bamboos introduced into Europe, and was well established as a hothouse plant by the late 1700s. The actual origins of the species is uncertain.

Its rhizomes may extend up to 2/4 ft. before turning upward, creating open, relatively fast spreading clumps. Bambusa vulgaris is an attractive ornamental timber bamboo. Its shoots are edible, though bitter. Although the starchy culm wood is vulnerable to powder post beetle attack and is relatively soft, the culms are often used for scaffolding and basic construction. Long culm fibers, rapid growth, and ease of propagation recommend B. vulgaris as a choice source of pulp for paper production. Although there are reports of sporadic flowering, B. vuilgaris has never had a period of gregarious flowering that periodically decimates most other bamboos.

Because of this, B. vulgaris is all the

more valuable as a reliable and predictable commercial resource.

Bambusa vulgaris ‘Vittata’ Common

Maximum

name: painted bamboo height: 50 ft. (15 m)

Maximum

diameter:

Minimum

temperature:

4 in. (10 cm) 27°F

(—3°C)

Light: full sun A variegated form of Bambusa vulgaris, ‘Vittata’ is a highly attractive, large ornamental bamboo. Its culms are golden-yellow, with green vertical striping of varying widths. The

16 ft. (5 m) 27°F

(—3°C)

Light: full sun Depending on one’s taste, ‘Wamin’ is a somewhat bizarre looking cultivarof Bambusa vulgaris. The lower internodes are swollen and very short, dwarfing the plant. Grown as an ornamental, it requires pruning to look its best. Some selections show additional variations, such as light green culms with darker green stripes.

25

x

Bambusa

258

Chapter 9: Bamboo Genera, Species, and Cultivars

Bashania

digenous bamboos. Of the 20 hardiest selections, 17 were Phyllostachys. Bashania fargesii was one of the three that were not Phyllo-

A relatively new genus consisting of six known species, Bashania was previously included in Arundinaria. Rugged and hardy, Bashania bam-

stachys, but still ranked in the top 20 for hardi-

boos are endemic to the mountainous regions

ness (Qui and

of central China, where they share forest habitats with broad-leaved trees and conifers. They are also sometimes found in pure stands. The bamboos are medium sized and have leptomorph rhizomes.

Bashania faberi

Common synonyms: Arundinaria fangiana, Bashania fangiana, Gelidocalamus fangianus

Maximum

height:

10 ft. (3 m)

Maximum

diameter:

Minimum

temperature:

4 in. (0.6 cm)

10°F (—12°C)

Light: mostly sunny Bashania faberi is a shrub bamboo with many branches in clustered tufts at each node. It is distributed in the Chinese provinces of Sichuan,

Shaanxi, Gansu, and Ningxia, and

can be found at elevations of more than 12,000 ft. (3700 m). The species is more commonly known

by variations of the name “fangiana,”

including Arundinaria fangiana, B. fangiana, and Gelidocalamus fangianus.

Bashania fargesii

Common synonyms: Arundinaria fargesii Maximum height: 30 ft. (9 m) Maximum

diameter:

2 in. (5 cm)

Minimum

temperature:

0°F (—18°C)

Light: mostly sunny

Distributed in the Shaanxi, Hubei, and Gansu Provinces of China, Bashania fargesii is a rugged plant with thick culm walls and tough, robust leaves. The culm and branch leaf sheaths are persistent or late in shedding. Initially, there are three branches at each node, later becoming many. Sixty-four species of bamboo were evaluated in winter hardiness trials designed to select the best bamboos for the Beijing area in China, a region with hard winters and no in-

Ma

1992).

Borinda

A recently described genus of attractive, Old World, montane bamboos, Borinda is composed of 18 species that had previously been assigned primarily to Fargesia, as well as to Arundinaria, Thamnocalamus, and Yushania. Placement of these bamboos has been problematic. In China, two schools of thought sought to place these species either in Yushania, based primarily on the structure of the flowering parts, or in Fargesia, based primarily on rhizome form and other vegetative characteristics. Both approaches proved problematic, and ultimately untenable. The research of C. M.A.

Stapleton

(1998b) of the Royal Bo-

tanic Gardens, Kew, led to the establishment of a new genus, Borinda. Nearly all Borinda species have fine longitudinal ridges on either the culm internodes or the branch internodes—or both, distinguishing them from Fargesia and most other genera. Borinda generally resembles Thamnocalamus, but it differs by having up to seven branches in the first year, including two that extend behind the culm. Thamnocalamus has fewer first year branches, none extending behind the culm. Borinda culm internodes are long and usually finely ridged. Those of Thamnocalamus are shorter and smoother. Borinda has a pachymorph rhizome system with short rhizome necks, and forms clumps with culms less than 12 in. (30 cm) apart, distinguishing it from Yushania, with its typical, long-necked rhi-

zomes.

Borinda foliage leaves are tessellated, and the bamboos have some frost hardiness, though less than the more frost hardy species of Fargesia, Thamnocalamus, and Yushania. The

foliage leaf blades of Borinda are thin, soft, and

o

ov

s)

°

8

il

§(=

° ° 2

bs}

a

9 a

=

3

a Lic}

rs 3

i

260

Chapter 9:

Bamboo

Genera,

Species, and Cultivars

pliable, with a matt finish. The high altitude species of Borinda are deciduous in the winter. Yushania bamboos have tougher glossy leaves, and typically remain evergreen.

New Borinda

shoots often have a tuft of long, generally erect, leaf blades at the apex. Borinda are distributed along a continuous chain of mountain ranges, at elevations ranging from 6000 to 11,800 ft. (1800 to 3600 m),

or possibly even as high as 13,800 ft. (4200 m), from Annapurna in western Nepal and Tibet, across to China’s Yunnan Province, and down to within

150 mi. (240 km) of Ho Chi Minh

City (Saigon)

in southern

Vietnam.

Some highly attractive evergreen species

sequently renamed Yushania boliana in honor of Gerald Bol. However, neither Himalayacalamus nor Yushania are appropriate genera for the plant. Molecular evidence and morphological features such as branching structure indicate that it belongs in the same clade as Fargesia, Yushania, and Borinda (Chris Stapleton, personal

communication). At the moment Borinda is the best match, but its genus could change yet again, possibly to a completely new genus of its own. Regardless of the difficulties in nomenclature, it is a very desirable ornamental.

Borinda fungosa

just coming into cultivation in the Western

Common synonym: Fargesia fungosa

world include Borinda fansipanensis, B. grossa, B. hygrophila, B. macclureana, B. papyrifera, and B. perlonga. Borinda can be separated into two

Maximum

height: 20 ft. (6 m)

Maximum

diameter:

Minimum

temperature:

groups, larger evergreen species, and smaller

deciduous species found at higher elevations. Although additional species may become known, the deciduous group presently consists of only three species, B. emeryi, B. frigidorum,

Light: partial shade Formerly classified as a Fargesia, which it generally resembles in form, Borinda fungosa has somewhat larger leaves than many Old World montane bamboos, up to 64 in. (16 cm)

and an additional species from

long and %

Sichuan.

(Sta-

pleton 1998b; personal communication).

Borinda boliana Common

synonyms:

medius (hort.),

Himalayacalamus inter-

Yushania boliana

Maximum

height: 50 ft.

Maximum

diameter:

Minimum

temperature:

(15 m)

2 in. (5 cm)

10°F (—12°C)

Light: partial shade Borinda boliana is a large, robust, highly attractive montane bamboo. The new culms

are bright pale blue-green, sometimes turning reddish purple with age. The true identity of this bamboo

remains something of a mystery.

It was reportedly collected in the mountains of Sichuan, China, and brought to Japan in the late 1980s. From Japan, Gerald Bol, former president of the American Bamboo Society, introduced it to the West under the provisional name Himalayacalamus intermedius. It was sub-

| in. (2.5 cm) 15°F

(—9°C)

in. (1.7 cm) wide. An attractive or-

namental, it is more cold sensitive than the Fargesia bamboos in cultivation, but more heat tolerant. Though small, the shoots are reportedly good tasting. The culms are used in weaving. Native to China’s Yunnan and Sichuan Provinces, it is distributed at an elevation range of 6000

to 8900

ft. (1800

to 2700

m). A gregar-

ious flowering in the early 1990s resulted in wide distribution of the seedlings in America, Europe, and elsewhere.

Brachystachyum A genus comprised of one species and an additional variety, Brachystachyum is a shrublike leptomorph genus native to China. The culms are round, with a slight compression on the branching side of the internode. Each node has three principal branches. Brachystachyum generally resembles Semiarundinaria, but its floral parts are much shorter.

Gj ac]& 2)

ie

zt

g 3 a 2=) % AS = 5 a

262

Chapter 9: Bamboo Genera, Species, and Cultivars

Brachystachyum densiflorum Maximum

height:

10 ft. (3 m)

Maximum

diameter:

Minimum

temperature: 0°F (—18°C)

2 in. (1.25 cm)

Light: partial shade Brachystachyum densiflorum is similar in appearance to a smaller scale Semiarundinaria. The culm leaves shed promptly. The foliage leaves are up to 7 in. (18 cm) long and 1 in. (2.5 cm) wide.

Brachystachyum densiflorum var. villosum Maximum

height: 10 ft. (3 m)

Maximum

diameter:

Minimum

temperature:

4 in. (1.25 cm) 0°F (—18°C)

Light: partial shade Similar to the principal type, Brachystachyum densiflorum var. villosum differs by having a mass of yellowish brown hairs at the base of the culm leaf sheath.

Cephalostachyum

Cephalostachyum includes tropical bamboos with pachymorph rhizome systems that range in appearance from shrublike, to climbing, to tall and treelike. The culms are generally slender and thin walled. The genus consists of some

16 known

species.

Cephalostachyum pergracile

Common

synonym: Schizostachyum pergracile

node. It is a striking specimen in the land-

scape.

Cephalostachyum pergracile is used for construction, paper pulp, and basket, mat, and crate weaving. Split culms are used to make fishing rods. Locally, rice is boiled in the culm joints, flavoring the rice and making a convenient carrying vessel for travel.

Chimonobambusa

Chimonobambusa bamboos typically spread aggressively, and they range in size from shrublike to medium-sized and treelike. Unusual for bamboos with leptomorph rhizomes, they typically shoot in fall or winter. Although well adapted to its native environments, Chimonobambusa does not always fit perfectly in other climates. Some species are moderately winter hardy, but the tender shoots that come in fall and winter are readily susceptible to cold damage, disrupting the plant’s growing cycle and threatening its health. If fall and winter shoots are damaged or destroyed, Chimonobambusa often compensates by shooting again in the spring and summer. These out-of-cycle shooting periods may permit the plant to survive and grow, but without the vigor a normal growth cycle would provide. Bamboo shooting generally occurs earlier in warmer areas than in cooler areas, but Chimonobambusa behaves in an opposite manner,

shooting earlier in cooler areas and later in

Maximum

height: 40 ft. (12 m)

warmer areas. In its native environment,

Maximum

diameter:

Minimum

temperature:

species of Chimonobambusa yields three times as many pounds of shoots per acre in higher, cooler areas than it yields in lower, warmer

2%

in. (7 cm) 32°F

(0°C)

Light: mostly sunny A tender, tropical bamboo, Cephalostachyum pergracile is known for both its beauty and utility. Native to India and Burma, and widely cultivated in China’s Yunnan Province, it is a very attractive arborescent bamboo with tufted foliage and nodding culm tips. The culm leaf sheaths are shiny, leathery, and chestnut brown, covering about a third of the inter-

areas

(Wen

one

1994).

In China, Chimonobambusa is found at elevations of 300 to 6600 ft. (90 to 2000 m). These

are short-day, understory plants that thrive when the forest canopy reduces sunlight by about 60 percent. Chimonobambusa plants typically bear three principal branches at each node. The nodes are

Chimonobambusa

prominent, and the lower nodes of some species have aerial roots or spines. This latter feature helps to distinguishethis genus from the genus Qiongzhuea, which lacks aerial roots or

spines. Qiongzhuea is very closely related to Chimonobambusa, and some taxonomists regard Qiongzhuea as a section within Chimonobambusa In this book, Qiongzhuea is treated as a separate

genus. Evidence supports both treatments, and thus does not definitively validate either. In addition to the controversy regarding the status of Qiongzhuea as a separate genus, there are also differences of opinion regarding the assignment of individual species (Clark 1995).

According to tradition, the proper measurement was from the nipple of the right breast to the end of the middle finger of the outstretched left hand, of which the handle took up six sun, and the remainder must have thirty-three nodes. Such were called yurushi muchi (the right to use them being reserved to riders who had special permission from their ridingmasters) and they were highly valued by teachers of equitation, but the whips with thirty-three knots were very rare.

Chimonobambusa marmorea f. variegata Maximum

height: 8 ft. (2.4 m)

Chimonobambusa marmorea

Maximum

diameter:

Minimum

temperature:

Maximum

height: 8 ft. (2.4 m)

Maximum

diameter:

Light: partial shade Similar to the principal form, except that the leaves have narrow white stripes.

Minimum

temperature:

Common

name: marbled bamboo %4 in. (2 cm) 15°F

(—9°C)

Light: partial shade Although Chimonobambusa marmorea likely originated in the Honshu district of Japan, other authorities place its originsin the Guangxi region of China. It was introduced into Europe in 1889. Itsname derives from the marbled appearance of the new shoots and culm leaf sheaths. New shoots include purple and cream colorations. The new shoots are initially without branches, branching out near the top of the culm the following summer, then branching further down the culm in subsequent years. The culm leaves are longer than the internodes, and tardy toshed. Although small, the shoots reportedly have exceptionally good flavor. The culms are very thick walled. This species is an attractive

but aggressive runner. Once highly valued as whips, the rhizomes of Chimonobambusa marmorea were at one time restricted for use only by the Shogun. Rhizomes with tightly spaced nodes were preferred. In his 1899 work, The Cultivation of Bamboos in Japan, Sir Ernest Satow relates:

% in. (2 cm) 15°F (-9°C)

Chimonobambusa quadrangularis

Common

name: square bamboo

Maximum

height: 25 ft. (7.5 m)

Maximum

diameter:

Minimum

temperature:

1

in. (4 cm) 15°F (—9°C)

Light: mostly sunny

Native to southeast China, Chimonobambusa quadrangularis is an attractive ornamental

bamboo with distinctive squarish culms, a trait that is most pronounced in established groves with mature culms. The lower nodes have small, spinelike root primordia. The culm walls are thick, but not very strong. They are used as walking sticks and for craft items, but are unsuitable for construction or weaving. There are no records of this species flowering. The shoots, coming in the fall, are regarded as choice edibles.

Chimonobambusa quadrangularis

‘Suow’

Maximum

height: 25 ft. (7.5 m)

Maximum

diameter:

12 in. (4 cm)

263

264

Chapter 9:

Bamboo

Genera,

Species,

and

Cultivars

Chusquea is closely related to Neurolepis.

Lynn

G. Clark, the authority on Chusquea, suggests that the genus probably originated in what is now Brazil, subsequently

radiating to the Andes

and Central America (Clark 1997b).

Central

American, Andean, and high-altitude species appear to be more recently evolved. Despite the

considerable diversity, morphological and molecular analyses show that the genus is monophyletic—that is, all Chusquea species are descendant from a common ancestor. The natural habitat for Chusquea ranges from northwestern Mexico to the West Indies to southern Chile and Argentina, at altitudes ranging from sea level to more than 14,000 ft. (4300 m), from tropical lowlands to highaltitude grasslands and pine forests (Judzie-

wicz and Clark 1991). Many chusqueas inhabit open, Chimonobambusa

quadrangularis,

showing the aer-

ial roots or spines on the nodes characteristic of some Chimonobambusa species. Author's Garden

high-elevation grasslands called paramos

and the slightly lower elevation subpdramos habitats that are windy, humid, and rainy. Daily temperature fluctuations typically exceed seasonal fluctuations. The nights are cool,

dipping to near freezing or below, followed by Minimum

temperature:

Light: mostly

daytime temperatures sometimes

15°F (—9°C)

the upper 60s (about 20°C)

sunny

Similar to the type form, but the culms are yellow

with a few green stripes of varying

width. The foliage leaves may

have

occasional

variegation.

Chusquea

reaching to

(Judziewicz et al

1999). At their southernmost

extension, chus-

queas are ubiquitous in the beech

forests of thé

cool temperate zone of southern Chile. Although most chusqueas inhabit higher elevations and montane environments, such as the montane cloud-shrouded

regions of the Andes,

A New World counterpart to the Old World’s

where precipitation is primarily

“mountain

form of fog and mist, some species, including

bamboos,”

the genus Chusquea is

associated with the Andes, just as many

of the

Old World’s mountain bamboos are associated with the Himalayas. There is even somewhat of a corollary between China’s giant panda and the speckled bear of the central Andean cloud

received in the

the earliest evolving of the chusqueas, are native to the hot, sunny lowlands. More than a third of the named

Chusquea species, and the

majority of the undescribed species, are indigenous to the Andes, where all major groupings

forests. Like the giant panda, the highly reclusive speckled bear is believed to feed on bamboo—although, in the case of the speckled

of Chusquea are represented

bear, not as an exclusive food.

single population. From both a latitude and altitude standpoint, Chusquea has a broader distribution than any other bamboo genus.

New Chusquea

shoots are reportedly part of the speckled bear’s dining habit

(Judziewicz

et al.

1999).

(Clark

1997b).

Some species have a wide geographic distribution, while others are known

to exist in only a

Chusquea

Although a few chusqueas are quite cold hardy, most are relatively tender, which would seem to limit them to the warmest parts of the United States. However,

most chusqueas are

not heat tolerant either. Warm nights and warm soil temperatures are particularly problematic for many of the species, especially the hardier ones. A few species do match up quite well with some American growing climates, however. Many of the chusqueas introduced into the U.S., for example, thrive in the fogshrouded environment of California’s San Francisco Bay area. It is regrettable that a broader spectrum of the genus is not well suited to more American growing climates. Many chusqueas are quite beautiful ornamen-

C. fendleri, and C.

candens, have amphimorph

rhizomes (Judziewicz et al. 1999), As more

species are investigated, the possibility remains that chusqueas with strictly leptomorph rhizome systems will be found. Chusquea is one of only two bamboo genera

that truly have multiple branch buds at the culm node—although at least one species, C. smithii, generally develops only a single branch at each node (Clark

1997b). In some

Chusquea species, the bud complement is quite complex, with sometimes

numerous buds, of

up to three sizes, arranged in various configu-

rations. Except for C. cu/eou, C. juergensii, and a few species in subgenus Swallenochloa, there is a pronounced size difference between the large central bud and the smaller subsidiary buds (Judziewicz et al. 1999). Typically, the sub-

tals, and it is worth the effort to explore them. The genus Chusquea was first recognized in 1822. Its name is derived from chusque, the name given to the bamboo by the indigenous peoples of Colombia and Ecuador (Judziewicz

central bud in a crescent shape, but in some species, such as C. pittieri, they may be arranged

etal. 1999), Among

in a whorl around the circumference of the

the native uses for Chus-

quea are construction, forage, fencing, and craft, including tools, furniture, decorative ornamental baskets, and sturdy baskets for transporting fruit and produce. Of an estimated 200 Chusquea species, only

about two-thirds have yet been named and taxonomically described. A few species exist only as herbarium

specimens,

having become

extinct in the 20th century. For Chusquea, the culm leaf and bud complement are sufficient to determine species in nearly all cases (Clark 1989). The research by Lynn G. Clark has greatly expanded our knowledge of this unusual genus. Solid culms are a distinctive characteristic of Chusquea, although the pith in older culms of some species may break down, forming hollows in the culm, and among the more recently evolved chusqueas, at least two known species have hollow culms—an evolutionary reversal. In the main, however, solid culms remain a typifying characteristic. Most Chusquea species have pachymorph rhizomes, but two,

sidiary buds are arrayed around or below the

node. In some species, the subsidiary buds can number

as many

as 80 or more

(Clark

1989).

These branching patterns are fascinating to

observe, particularly as the new buds begin to emerge from the culm. A common feature in many bamboos, fimbriae, or fringelike hairs, are entirely lacking on Chusquea culm leaf sheaths. Similarly, auricles are never present

(Judziewicz

et al. 1999),

Flowering cycles vary widely in the genus, from as short as 2 to 3 years, to as long as 60 to 70 years in the case of C. pittieri. The species in Chusquea subgenus Swallenochloa tend to flower at shorter intervals (Judziewicz et al. DOES

The genus Chusquea is subdivided into three subgenera: Rettbergia, Chusquea, and Swallenochloa, in order of their evolutionary emergence. Each subgenus is presumed to be monophyletic—all members of each subgenus are derived from the same common ancestor. So far, the evidence for this is strongest for Ret-

thergia. Some species have not yet been as-

265

266

Chapter 9: Bamboo Genera, Species, and Cultivars

signed a subgenus, and some subgenera contain additional informal groups within them. Further study is likely to yield additional evolutionary groupings within Chusquea (Judziewicz et al. 1999),

Chusquea subgenus Rettbergia

States. None are currently in cultivation. The subgenus consists primarily of Brazilian species. Examples of this subgenus include Chusquea bahiana, C. bambusoides, C. capitata, C. capituliflora, C. oxylepis, C. sellowii, and C. urelytra (Clark

1997b).

The earliest Chusquea forms, identified with

Chusquea subgenus Chusquea

subgenus

Culm diameters in subgenus Chusquea range

Rettbergia, have characteristics associ-

ated with a clambering habit, including sharply bending branches, particularly at the lower nodes, infravaginal branching, and a horizontally emerging central branch bud that may be adaptive for scrambling support. The culms typically hang or trail as they scramble opportunistically over and through any convenient supports. The culm leaves have a rough, gripping texture that also assists the clambering habit. The branching habit is distinctive. Referred to as starburst or arachnoid (spiderlike), the branches are bent sharply at one of the lower nodes such that they radiate away from the culm and one another in a starburst pattern that also resembles the bent legs of a spider (Judziewicz et al, 1999), Culm

diameters range from io in. (2 mm)

to % in. (2 cm), culm lengths from 5 ft. (1.5 m) to 50 ft. (15 m). The internodes are round or, rarely, slightly flattened just above the branch

complement, sometimes glaucous, but never waxy. A few species have fine hairs just below the node. Culm leaves are persistent. At midculm, the nodes have a single, usually circular branch bud, surrounded by 4 to 30 smaller branch buds of equal size. The foliage leaves are untessellated and generally pliable. Many species of this subgenus inhabit hot,

sunny lowlands and have an unsavory reputation for weedy, aggressive growth that threatens more desirable vegetation (Judziewicz et al. 1999), A few are far less aggressive, and quite delicate and attractive. The members of the subgenus are quite tender, however, and only potentially suited to the outdoors in a very few of the warmest climates in the United

from 4 in. (0.6 cm) to 24 in. (6 cm), culm lengths from 5 ft. (1.5 m) to 82 ft. (25m).

Culms are erect at the base, becoming arching or clambering, hanging, or sometimes trailing off supports. Internode characteristics vary among the species from round to flattened or shallowly or deeply grooved above the branch complement. The solid internodes may become hollow with age. The internodes vary in surface coating and texture, but are usually not waxy. The culm leaves are not rapidly shedding, and they may be persistent. At mid-culm, the nodes have a single, usually triangular but sometimes circular, branch bud surrounded by two to numerous smaller buds of sometimes two sizes, with thorny root primordia present in some species. Branching is either infravaginal or extravaginal. The subsidiary branches sometimes rebranch. Foliage leaves are untessellated, or only weakly tessellated, and are generally pliable. The Chusquea subgenus is largely Andean and Central American. Some bamboos within the subgenus are aggressive colonizers. When disruption occurs in their mountain forest habitats, their aggressive nature can have a major ecological impact. The type species for the subgenus is C. scandens, but the bamboos in this subgenus show considerable diversity, and groupings that are already known within the subgenus suggest that additional subgenera may be indicated. Additional species in subgenus Chusquea include C. circinata, C. coronalis, C. cumingii, C. fendleri, C. liebmannii, C. macrosta-

chya, C. pittieri, C. quila, C. simpliciflora, C. uliginosa, and C. valdiviensis (Judziewicz et al. 1999).

Chusquea

Chusquea subgenus Swallenochloa

are narrower.

Like those of C. coronalis, C. pit-

Short, waxy internodes and a shrubby habit typify subgenus Swallenechloa. Culm diameters range from io in. (2 mm) to 24 in. (6 cm), culm lengths from 10 ft. (3 m) to 60 ft. (18 m). The culms are usually erect, sometimes arching toward the tip. The short internodes are round to slightly flattened or grooved above the branch complement. Young culms are solid, but may become less so with age, and are usually covered with a thin waxy coat. Primarily because of the tendency toward hollow culms, Swallenochloa was once regarded as a separate

tieri, and C. liebmannii, the branches of C. circinata grow ina whorl around the circumference of the culm, and spiny root primordia form at the nodes.

Branching is more linear than clustered, and the branches are usually erect. Deciduous in a few species, the culm leaves are usually persistent but eventually disintegrate and shed. At mid-culm, the nodes typically have a single, usually triangular branch bud, surrounded or flanked by one to numerous smaller buds of sometimes two sizes. Branching is intravaginal

ico to Costa Rica. As with other members

genus.

or extravaginal. Subsidiary branches usually rebranch. Foliage leaves are often stiff and sometimes tessellated (Judziewicz et al. 1999),

Chusquea coronalis Maximum

height: 23 ft. (7 m)

Maximum

diameter:

Minimum

temperature:

%4 in. (2 cm) 26°F

(—3°C)

Light: partial shade A highly desirable but somewhat temperamental ornamental, Chusquea coronalis is native to warm lowlands and cloud forests from Mexof

section Verticillatae of subgenus Chusquea, this species produces branches in a whorl around the circumference of the culm. Chusquea coronalis is a delicate bamboo, with a profusion of subsidiary branches and foliage leaves arrayed more or less horizontally. One of the more widely cultivated bamboos of the genus, it prefers a moist habitat and moderate sun. In cultivation in the United States, this species typically experiences a significant leaf

Most of the species in subgenus Swallenochloa can tolerate a light frost, and some are far hardier. Most are native to high-altitude grasslands, but a few may occur in a range of forest environments. The forest species are generally more rugged and have longer internodes and arching culms (Clark 1997b). Examples of this subgenus include the various forms of Chus-

drop in winter, leafing out again and regaining

Maximum

height: 25 ft. (7.5 m)

quea andina, C. culeou, C. heterophylla, C. mon-

Maximum

diameter:

tana, and C. nudiramea (Judziewicz et al. 1999).

Minimum

temperature: 0°F (-18°C)

Chusquea circinata

its delicate attraction with the changing seasons. Dry, indoor conditions, particularly in winter, will cause it to suffer.

Chusquea culeou Common

synonym: Chusquea breviglumis 1/2 in. (4 cm)

Maximum

height: 22 ft. (7 m)

Light: mostly sunny Among the most widely cultivated species of all the chusqueas, finding its way to both

Maximum

diameter:

American and European

Minimum

temperature:

| in. (2.5 cm) 26°F

(—3°C)

Light: mostly sunny This species somewhat resembles Chusquea coronalis, but is not as ornamentally impressive. The subsidiary branches of C. circinata are coarser and more erect, and the foliage leaves

gardens, Chusquea

culeou is one of the hardiest of the genus. It is among the few chusqueas in which there is no pronounced difference in branching size between the central branch bud and the subsidiary buds, the multiple branches all appearing generally equal.

267

Chusquea

circinata.

Quail Botanical Gardens

Chusquea coronalis. Quail Botanical Gardens.

270

Chapter

9: Bamboo Genera, Species, and Cultivars

A polymorphic species responsive to environmental conditions, Chusquea culeou exhibits

significant variation in form. The culms are erect to leaning. The leaf size of some forms is up to three times larger than that of other forms. Under strong sun, C. cu/eou has a more

compact, shrubby form, with smaller branches. In more shaded conditions, it is taller with longer branches and a more open habit. Chusquea culeou is a dominant

understory

plant in the southern Andean beech forests of its native Argentina and Chile. It forms dense stands where the overstory has been disturbed or eliminated, such as by fire or logging. Culms of this species have been estimated to live up to 33 years. The flowering cycle is said to be approximately 45 years (Judziewicz et al. 1999). Chusquea breviglumis is synonymous

with

culeou ‘Cana Prieta’, is derived from the Spanish words meaning blackish or very dark cane. The culm leaves may persist, looking slightly disheveled, but they eventually disintegrate and diminish. ‘Cana Prieta’ prefers acidic soil to thrive and look its best, but will do well in soils that are only moderately acidic. As an experiment while propagating the plant, I placed one of the divisions in 100 per-

cent peat moss. As with my other container plants, I occasionally added fertilizer, but provided no special treatment. After a year, the plant showed no signs of suffering and, if anything, displayed more vigor with more vivid leaf color than the other propagules.

Chusquea aff. culeou

Common synonym: Chusquea gigantea

C. culeou. However, one of the bamboos in the garden trade that is sold under the name C. bre-

Maximum

height: 60 ft. (18 m)

viglumis is a different taxon, provisionally iden-

Minimum

temperature: O°F (—18°C)

tified as C. aff. culeou

Light: full sun Chusquea aff. culeou is one of two bamboos in the garden trade sold under the name C. breviglumis. True C. breviglumis is synonymous with C. culeou. Chusquea aff. culeou, however, may be a different taxon. Its true botanical name is uncertain, hence the provisional nomenclature. Believed to be a close relative of Chusquea culeou, it differs distinctively from that species by having one to three branch buds that are much larger than the other subsidiary buds, rather than the uniform array typical of C. culeou. In an individual culm’s second year, an additional one to three new large buds appear and generate even larger primary branches. In my relatively small clump, a central branch on

Chusquea culeou ‘Cafia Prieta’ Maximum

height:

10 ft. (3 m)

Maximum

diameter:

Minimum

temperature:

2 in, (1.25 cm) 0°F (—18°C)

Light: mostly sunny It is curious that some of bamboo’s worst

taxonomic muddles seem to reside with the Old World montane bamboos of the Himalayas and the New World montane bamboos of the Andes. Chusquea culeou ‘Cana Prieta’ is one

such bamboo. It is in widespread cultivation in the United States under the name C. nigricans. The accepted botanical name for C. nigricans is C. montana. However, the bamboo widely cultivated in the U.S. as C. nigricans is not C. montana, but a dwarf form of C. culeou that was collected near a bog in Chile. Regardless of its taxonomy, it is an attractive landscape plant, with relatively small, deep green leaves (see frontispiece photo). Its culms turn a very dark red-brown that is sometimes almost black. The cultivar name, Chusquea

Maximum diameter: 24 in. (6 cm)

one

14 ft. (4.2 m) tall culm measured nearly 5

ft. (1.5 m) in length. In field studies in Chile, Lynn G. Clark observed that C. culeou and C. aff. culeou appear to intergrade (Lynn Clark, personal communication), making demarcation of the taxa even more problematic. Reportedly based on a cultivated garden specimen in France, the plant has been de-

>

g ey

a ° } 2 f= o f)

°

4

% © 3

z

=] re GC

‘ Chusquea aff. culeou.

Author's garden

scribed and published with the name Chusquea

gigantea. However, since field studies have shown that intermediate forms exist in different populations, and have revealed the apparent intergrading of C. culeou and C. aff. culeou, publication of C. gigantea as a new

species may

Chusquea cumingii Maximum Maximum

height: 12 ft. (4 m) diameter: % in. (2 cm)

Minimum

temperature:

10°F (—12°C) estimated

Light: full sun Native to semiarid regions of central Chile,

be premature. Its status awaits further study. Some reports indicate that Chusquea aff. culeou is slightly less hardy than C. culeou, in

Chusquea cumingii

part because its new shoots are damaged by

nent when

frost. My C. aff. culeou produces shoots in the fall as well as in the spring, and the fall shoots are inevitably killed all or in part by the winter cold. Although the C. culeou growing in my garden is admittedly less well established than the C. aff. culeou, it seems to be slightly more abused by winter conditions than the C. aff. culeou, which, except for tender shoots, appears entirely unfazed.

portedly prefers somewhat alkaline soil, as would be expected given its semiarid native habitat. Chusquea cumingii is distinctive, and attractive, at least on a small scale. It may be hardier than the current estimate indicates.

As with most chusqueas,

has distinctive, small, stiff,

sharply pointed leaves with a blue-green colorcast. The leaf characteristics are most promigrown

in full sun. This species re-

Chusquea aff. culeou

performs far better in the ground than ina container. It is an exceptionally vigorous plant, and its pachymorph

rhizomes have rather long

necks, creating an open, relatively rapidly spreading clump. The culms quickly increase in size from year to year. The partially brown

culms can be striking, though

redthey

are

often partially covered with tattered culm leaves, giving a slightly

unkempt

appearance.

Stripping the culm leaves enhances

the plant’s

appearance, as does pruning back the large dominant branches if they get out of hand. The long rhizome necks and the irregular association of roots with individual portions

of the plant make propagation of larger specimens rather challenging. One inevitably ends up with sections of the plant that are unsuited for propagation. As a side benefit, however, the new shoots and rhizomes from these sections are fair game for the table. The rhizomes taste

excellent.

The

more

mature

shoots

are

somewhat bitter, but can be tamed by parboiling.

Chusquea cumingii. Author's garden

274

Chapter 9: Bamboo Genera, Species, and Cultivars

Chusquea foliosa Maximum

height: 65 ft. (20 m).

Maximum

diameter:

2 in. (5 cm)

Minimum temperature: 24°F (—4°C) Light: mostly sunny Indigenous to Chiapas, Mexico, and the montane, oak, cloud forests of Costa Rica, at elevations of 7200

to 8500 ft. (2200 to 2600 m),

Chusquea foliosa grows in gaps in the tree canopy. It is common on the slopes of Costa Rican volcanoes. The culms are erect at the base, then begin an arching habit. This species has unusual infravaginal branching that is shared by several

est habitats and tolerates the driest conditions. Like those of C. pittieri and C. circinata, its branches grow in a whorl around the circumference of the culm, and it has spiny root primordia at the nodes. Somewhat uncommon for the genus, the culm leaves are rapidly deciduous, exposing a clear view of the culm. And somewhat unusually for bamboos in general, when stressed, the leaf blades fold together along their length rather than rolling up.

Chusquea macrostachya

other chusqueas. The branches emerge by pop-

Maximum

height: 20 ft. (6 m)

ping out without long and is a very

Maximum

diameter:

Minimum

temperature:

at the base of the culm leaf sheath rupturing it. The foliage leaf blades are narrow with a smooth undersurface. It desirable ornamental.

Chusquea galeottiana Maximum

height:

50 ft. (15 m)

Maximum

diameter:

Minimum

temperature: 26°F (—3°C) estimated

% in. (1.5 cm)

Light: mostly sunny Chusquea galeottiana is a member of section Verticillatae of subgenus Chusquea. Like the other members of the section, C. galeottiana has

branches that grow in a whorl around the circumference of the culm. Within the section, only C. galeottiana and C. pittieri routinely grow at elevations higher than 6500 ft. (2000 m).

The culms are erect at the base, then arch broadly, befitting its clambering, climbing habit. It is indigenous to Oaxaca and Guerrero, Mexico

(Clark

1989).

Chusquea liebmannii Maximum

height: 33 ft. (10 m)

Maximum

diameter:

Minimum

temperature:

1 in. (2.5 cm)

32°F (0°C)

Light: mostly sunny Unlike most chusqueas currently in cultivation, Chusquea liebmannii tolerates periods of dryness. Among its native habitats are pine and oak forests from Mexico to Costa Rica. Of all the chusqueas, this species grows in the dri-

1% in. (4 cm) 0°F

(—18°C)

Light: mostly sunny Along with Chusquea culeou and C. montana, C. macrostachya thrives as an understory plant in its native environment in the beech forests of Argentina and Chile. Among the hardiest of the chusqueas, it is also a choice ornamental, with delicate leaves and arching culms and

branches. As with some other bamboos, if the

culm is damaged, a primary branch can elongate and effectively take the place of the culm. Many of the plants cultivated in the United States as Chusquea macrostachya are misidentified and are actually C. culeou. The two species can be readily distinguished, however. Chusquea culeou branches are all approximately the same size, and the leaf blades are relatively stiff. Chusquea macrostachya has a dominant branch per node, which is subtended by a number of smaller subsidiary branches. Its leaf blades are relatively soft compared to those of C. culeou (Lynn Clark, personal communication).

Chusquea mimosa ssp. australis Maximum

height: 16 ft. (5 m) estimated

Maximum

diameter:

Minimum

temperature:

2 in. (1.25 cm) estimated 22°F

(-6°C)

estimated

Light: mostly sunny Native to southeastern Brazil, Chusquea mi-

mosa ssp. australis is an attractive ornamental with small leaves on deep red culms. An un-

~

Chusquea

foliosa.

Quail Botanical Gardens

276

Chapter 9: Bamboo

Genera, Species,

and Cultivars

common feature for chusqueas, the leaf sheaths drop away to expose the branches.

Chusquea montana Common

synonym: Chusquea nig. icans

Maximum

height:

10 ft. (3 m) estimated

Maximum diameter: 2 in. (1.25 cm) estimated Minimum

temperature: 0°F (-18°C) estimated

Light: mostly sunny

Chusquea montana is the accepted name for C. nigricans. The plant cultivated in the United States under the name C. nigricans, however, is a dwarf form of C. culeou, and not C. montana (see C. culeou ‘Cana Prieta’). Chusquea montana is uncommon

in cultivation.

Chusquea montana is part of the understory in the beech forests of Argentina and Chile. Capable of thriving in subalpine conditions, it is somewhat

smaller and more delicate than

many of the other hardy chusqueas. Its swollen nodes are a distinguishing feature.

Chusquea muelleri Maximum

height: 6 ft. (1.8 m)

Maximum

diameter:

Minimum

temperature:

/% in. (0.6 cm)

32°F (0°C)

capable of achieving considerable heights without exhibiting any type of climbing behavior, though its culms are heavily arching (Lynn Clark, personal communication). Like Chusquea liebmannii and C. circinata, this species has spiny root primordia at the nodes. It has the longest flowering cycle of any Chusquea, an interval of some 60 to 70 years. Unlike typical Chusquea, in which branches are arrayed in a crescent shape around or below a larger central branch, the branches of C. pittieri grow in a whorl around the circumference of

the culm, like other members of section Verticillatae of subgenus Chusquea. Within the section, only C. galeottiana and C. pittieri routinely grow at elevations higher than 6500 ft. (2000 m). The branching is extravaginal, with branches bursting through the culm leaf sheath, but the culm leaves then generally fall away as the branches develop, exposing the culm. Chusquea pittieri is attractive on a smaller scale as well as a larger scale, surviving nicely and handsomely as a house plant. It is quite tolerant of dim winter light and dry conditions, as long as one can accommodate considerable winter leaf fall and the plant’s abandonment of the smaller culms.

Light: mostly sunny From eastern Mexico, Chusquea muelleri is

Chusquea quila

one of 26 named species of Chusquea that do

Maximum

height:

not “fit” any of the three established subgenera. It is a small, delicate plant with trailing culms and up to six branches per node.

Maximum

diameter:

Minimum

temperature: 26°F (—3°C) estimated

Chusquea pittieri Maximum

height: 65 ft. (20 m)

Maximum

diameter:

Minimum

temperature: 26°F (—3°C)

2 in. (5 cm)

15 ft. (4.5 m) estimated 1 in. (2.5 cm) estimated

Light: mostly sunny Chusquea quila is an aggressive colonizer in disturbed forest areas. It is similar to C. valdiviensis, though smaller. In the past, C. valdiviensis has been sold as C. quila.

Light: mostly sunny Chusquea pittieri is one of the largest and

Chusquea simpliciflora Maximum

height: 82 ft. (25 m)

most robust species of the genus. It is native to

Maximum

diameter:

Central America and Mexico. In Costa Rica it forms dense stands on canyon walls, covering them with cascading foliage. When canyon walls are not at hand, the plant threads its way into trees, or arches and hangs on other convenient supports. In its native habitat, it is also

Minimum

temperature:

¥% in. (1 cm) 32°F (0°C)

Light: mostly sunny Native to tropical and lower montane forests of Central America and the northern regions of South America, Chusquea simpliciflora is a tender species with very slender culms. It

Chusquea uliginosa. Bamboo

Sourcery.

278

Chapter 9: Bamboo Genera, Species,

and Cultivars

vines, climbs, and hangs in surrounding vegetation. The subsidiary branches extend at least halfway around flower

the culm, It is believed to

approximately

every

30 years

Chusquea subtilis

Chusquea tomentosa

Maximum Maximum

height: undetermined diameter: undetermined

Minimum

temperature: 26°F (—3°C) estimated

Light: mostly sunny Indigenous to the Talamanca

From southern Mexico, Chusquea sulcata grows at middle elevations and exhibits an open clumping habit. The culms turn golden yellow with age, and they arch to form an attractive umbrella-shaped profile.

Range of Costa

Maximum Maximum

height: undetermined diameter: undetermined

Minimum

temperature:

26°F

(—3°C)

estimated

Light: mostly sunny

Chusquea sulcata

Indigenous to the montane oak forests of Costa Rica, Chusquea tomentosa prefers slightly drier conditions than some of the other chusqueas of the area, including C. foliosa and C. subtilis. It grows under the tree canopy, as well as in exposed gaps in the canopy, at elevations

Maximum

height:

of 8200

Maximum

diameter:

Minimum

temperature: 28°F (—2°C)

Rica, Chusquea subtilis has numerous

branches

per node and long, narrow foliage leaf blades.

Its populations are denser in more humid areas and along streams in montane forests.

15 ft. (4.5 m) 2 in. (1.25 cm)

Light: mostly sunny

to 9800

ft. (2500

to 3000

m). The

culms are erect at the base, then begin to arch. Chusquea tomentosa has an unusual, infravaginal branching habit that is shared by several other chusqueas. The branches emerge by popping out at the base of the culm leaf sheath without rupturing it. The foliage leaf blades are long and narrow with a velvety undersurface. Itis an attractive bamboo, with tufts of branches and foliage along the culm.

Chusquea uliginosa Maximum

height: 30 ft. (9 m)

Maximum

diameter:

Minimum

temperature:

| in. (2.5 cm) 10°F (—12°C)

Light: mostly sunny

In its native habitat in southern Chile, Chusquea uliginosa grows along the perimeter of seasonal wetlands.

It can clamber up to 30 ft. (9

m) high or more into trees. In the landscape, it can be pruned to an attractive strongly arching habit.

Chusquea valdiviensis

Chusquea valdiviensis. Bamboo Sourcery.

Maximum

height: 30 ft. (9 m)

Maximum

diameter:

Minimum

temperature: 20°F (-7°C)

Light: mostly sunny

1

in. (4 cm)

Dendrocalamus

Native to southern

Chile, Chusquea valdivien-

sis clambers to a height of 30 ft. (9 m).

It is an

aggressive coloniz -r in disturbed forested areas, often readily overwhelming other foliage. It is less appealing as an ornamental

than

many other chusqueas.

genus for both traditional and modern

Dendrocalamus

Comprising

calamus includes

econo-

mies. On the list developed by the Interna-

Dendrocalamus is a genus of arborescent Old World tropical bamboos with pachymorph rhizomes.

mus requires a semitropical or tropical environment. Most Dendrocalamus species are associated with areas of high rainfall or montane habitats, but D. strictus is a prominent exception, inhabiting lowlands and drier regions. Dendrocalamus is an economically important

52 known

the world’s

species, Dendrolargest

bamboos,

tional Network for Bamboo and Rattan, in cooperation with the International Plant Genetic Resources Institute, which delineated priority bamboos meriting focused research and wider

several reaching heights of 100 ft. (30 m) or

use, four Dendrocalamus were included among

more. Culms

the original

may

be up to 1

ft. (30 cm)

in

diameter. The large leaves are up to 20 in. (50 cm)

long and 4 in. (10 cm)

wide

in some

spe-

cies. Dendrocalamus generally resembles Bambusa, but unlike in Bambusa, the culm leaf auricles are either absent or not prominent, and Dendrocalamus does not include species with spiny branches. Some species of Bambusa are moderately cold tolerant,

whereas Dendrocala-

Dendrocalamus asper. Quail Botanical Gardens.

19 species: D. asper, D. giganteus, D.

latiflorus, and D. strictus

Dendrocalamus asper Maximum

height:

100 ft.

(30 m)

Maximum

diameter: 8 in. (20 cm)

Minimum temperature: 23°F (—5°C) Light: full sun Dendrocalamus asper is an attractive orna-

279

280

Chapter 9; Bamboo Genera, Species, and Cultivars

mental, and itis more cold tolerant than most

Dendrocalamus hamiltonii

of the genus. It is native to Southeast Asia and

Maximum

height: 80 ft. (24 m)

widely cultivated throughout

Maximum

diameter: 7 in. (18 cm)

tropical Asia. Its

culms are used for paper pulp and construction. It is also cultivated for its large and excellent tasting shoots. A single D. asper shoot can weigh up to 16 lb. (7.2 kg) or more (Cusack

1997).

Dendrocalamus brandisii Maximum

height: 100 ft. (30 m)

Maximum

diameter: 8 in. (20 cm)

Minimum

temperature: 28°F (—2°C)

Light: full sun Native to India and Southeast Asia, Dendrocalamus brandisii is among the world’s largest bamboos. The lower nodes are branchless, but

Minimum temperature: 27°F (—3°C) Light: full sun The culms of Dendrocalamus hamiltonii are sometimes erect, but often grow in a curved or arching fashion. Lower nodes are bare of branches. Upper nodes branch thickly. The quality of the culm wood is not as high as some of the other Dendrocalamus species, but it is nonetheless used for construction, vessels for water and milk, floats for rafts, fuel, paper pulp, and basket making. The young shoots are suitable for the table.

Dendrocalamus jianshuiensis

may have pronounced aerial roots. The thick-

Maximum

height: 60 ft. (18 m)

walled culms are used in construction, and the new shoots are harvested for the table.

Maximum

diameter:

Minimum

temperature: 28°F (—2°C) estimated

4%

in. (12 cm)

Dendrocalamus giganteus

Light: full sun Dendrocalamus jianshuiensis is native to China’s Yunnan Province, at an elevation

Maximum

height:

range of 2600 to 5000 ft. (800 to 1500 m). The

Maximum

diameter:

Minimum

temperature; 25°F (—4°C)

Common

synonym: Sinocalamus giganteus 100 ft. (30 m) 12 in. (30 cm)

Light: full sun The name of this species is an apt descriptor of the plant. Dendrocalamus giganteus, in close

young culms are covered with waxy powder and needlelike hairs. In the clump, the culms nod toward the tip. Cured culms are used in construction.

competition with D. sinicus, is the world’s largest bamboo. Indigenous to India, Burma, and Thailand, it is also cultivated in China’s Yun-

Dendrocalamus latiflorus

nan Province and in Taiwan, where it was in-

Maximum

troduced in 1966. It may not perform as well as the other giants of the genus if grown in a cooler climate. Lower nodes may be branchless for 40 ft. (12 m) or more. The leaves can be up

Minimum temperature: 25°F (—4°C) Light: full sun Dendrocalamus latiflorus is native to China. The culms have excellent buoyancy and are used for floats and making rafts, as well as for the typical uses of construction, crafts, and paper pulp. The young shoots are considered

to 20 in. (50 cm)

long and

4 in. (10 cm)

wide.

Its culms are used for building construction, boat masts, furniture, buckets, water pitchers, vases, and other crafts. The young shoots are suitable for the table. Comparative experiments with D. strictus indicate that D. giganteus is a preferable raw material for papermaking.

Common synonym: Sinocalamus latiflorus Maximum height: 80 ft. (24 m) diameter:

10 in. (25 cm)

delicious. Dendrocalamus latiflorus is one of the

more important bamboos for shoot production. In southern China and Taiwan, shoots average 9 Ib. (4 kg) each.

Dendrocalamus giganteus, at an entrance to the bamboo groves at Quail Botanical Gardens.

N

Chapter

9: Bamboo Genera, Species, and Cultivars

Dendrocalamus latiflorus ‘Mei-nung’ Maximum

height: 80 ft. (24 m)

Maximum

diameter:

Minimum

temperature:

Light:

10 in. (25 cm) 25°F

(—4°C)

full sun

Introduced

from Taiwan in the 1980s, Den-

drocalamus latiflorus ‘Mei-nung’ is similar to the principal form, but the culms and branches are

light green, striped with dark green. The large leaves have occasional yellow stripes.

Minimum

temperature: 28°F (—2°C) estimated

Light: full sun One of the smaller species of the genus, Dendrocalamus minor is native to China’s Guang-

dong, Guangxi, and Guizhou Provinces. Its culms are used for weaving and for farm tools and utility construction.

Dendrocalamus strictus Common

name: male bamboo

Dendrocalamus minor

Maximum

height: 60 ft.

Maximum

diameter:

Maximum

height:

Maximum

diameter: 2/4 in. (6 cm)

Minimum temperature: Light: full sun

26 ft. (8 m)

(18 m)

5 in. (13 cm) 30°F (-1°C)

Dendrocalamus strictus possesses neither great

beauty nor exemplary physical properties, yet it is perhaps the Old World’s most important tropical bamboo. It tolerates drought and low humidity, growing well in areas marginally suitable for other bamboos. The lower portion of the thick-walled culms is sometimes nearly solid, particularly in dry environments.

Dendrocalamus strictus is used by local populations for construction, furniture, mats, and

baskets. In India, it is extensively cultivated for paper pulp. Although other bamboos have superior pulping characteristics, the abundance and rugged nature of the plant has made D. strictus the foundation and mainstay of India’s paper industry.

Dendrocalamus yunnanicus Maximum

height: 82 ft. (25 m)

Maximum

diameter: 7 in. (18 cm)

Minimum temperature: 28°F (—2°C) estimated Light: full sun Distributed in northern Vietnam and the adjacent Chinese regions of Yunnan and Guangxi,

Dendrocalamus yunnanicus

has erect

culms with nodding tops. The culms of this large bamboo are used for construction, water pipes, and rafts. The shoots are reportedly delicious. Quail Botanical Gardens

—_ Dendrocalamus minor. Quail Botanical Gardens

284

Chapter 9: Bamboo Genera, Species, and Cultivars

Dinochloa

below about

A topical genus of some 27 species (or perhaps

mum

closer to 20, according to some authorities),

Above 6100 ft. (1850 m), Himalayacalamus, another genus of Himalayan montane bamboos that resemble Drepanostachyum, become increasingly prominent. Cold temperatures and the greater levels of UV light cause increasing leaf damage at higher elevations. Unlike those of truly hardy bamboos, the foliage leaf blades of Drepanostachyum are not tessellated. On a mature plant, in the first year of culm growth, each node has around 25 branches. In subse-

Dinochloa bamboos have a pachymorph

rhizome

system, large leaves, and a climbing habit. More than any other climbing bamboos, they exhibit a true vining habit, presumably in adaptation to their rainforest environment. To facilitate the climbing habit, the internodes zigzag, helping the culms twine around tree trunks and limbs,

and the culm leaf sheaths are rough at the base, helping to grip tree bark or other climbing surfaces. The primary branch bud is capable of taking the place of the culm in the event the culm is

damaged. The genus is native to China, Southeast Asia, and the Pacific Islands.

Dinochloa malayana Maximum

height: 30 ft. (9 m)

Maximum

diameter:

Minimum

temperature:

2 in. (1.25 cm) 28°F

(—2°C)

Light: partial shade A vining bamboo from Thailand and Malaysia, distributed along forest margins, from

near sea level to 1600 ft. (500 m).

Dinochloa scandens Maximum

height: 30 ft. (9 m)

Maximum

diameter:

Minimum

temperature:

12 in. (1.25 cm) 28°F

(-2°C)

Light: partial shade A tropical climbing bamboo with black culms and large leaves, Dinochloa scandens can be grown as a decorative indoor plant. Reportedly, the plants under this species name in the United States are actually D. malayana.

Drepanostachyum

Drepanostachyum is a genus of somewhat tender, montane bamboos that grow up to 16 ft. (5 m) tall and have pachymorph rhizome systems. It is found primarily at elevations of 3300 to 7200

ft. (1000

to 2200

m)

in the dry semi-

tropical forests of the Himalayas. In its native habitats, Drepanostachyum does not survive

1600 ft. (500 m), where maxi-

temperatures

can

reach

104°F

(40°C).

quent years, a node may have as many as 70

branches. The branches are similarly sized, and they wrap around much of the circumference of the culm (Stapleton

1994d,

1994c).

The new shoots of Drepanostachyum are very bitter and are not suited for the table. The genus is useful as forage or pasture for animals and, despite the somewhat swollen nodes, as weaving material. In the main, however, most species are not widely cultivated or harvested. Where available, other genera are more often favored. In their natural environment, Drepanostachyum bamboos are often heavily browsed by animals, and often do not reach their full height. Significant polymorphism is found among the known species, and additional species will likely be identified beyond the 11 currently named. Considerable confusion surrounds the identity and classification of many of the pachymorph montane bamboos. Drepanostachyum can be distinguished from Thamnocalamus by the absence of leaf tessellation and by branch buds, which, unlike in Thamnocalamus, are wider than they are tall. The identity problem is most acute between Drepanostachyum and Himalayacalamus. Not only are the genera frequently confused, but some of the species have long been interchangeably labeled in the nursery trade as well, exacerbating and perpetuating the problem. Several features distinguish the two genera. On the inside, upper part of the culm leaf sheath, adjacent to the ligule,

Drepanostachyum khasianum.

Quail Botanical Gardens.

286

Chapter 9:

Bamboo

Genera,

Species, and Cultivars

Drepanostachyum sheaths are rough, whereas Himalayacalamus sheaths are smooth.

Himalay-

acalamus branches differ from Drepanostachyum in that they vary in size, grow more erect, and are not arrayed as broadly around the circumference of the culm. Drepanostachyum is less cold tolerant than Himalayacalamus, but more

States as Himalayacalamus falconeri or Arundinaria falconeri, but itis a different species and has been given the name Drepanostachyum sengteeanum. It flowered gregariously in the 1990s, disclosing its identity as a Drepanostachyum. Analysis of the material sent by bamboo nurseryman

Gib Cooper to C. M. A. Stapleton

Common synonym: Sinarundinaria falcatum Maximum height: 12 ft. (4 m)

at the Royal Botanic Gardens, Kew, led to identification of a new species, D. sengteeanum (Chris Stapleton, personal communication). It is an attractive, tightly ctumping bamboo with relatively small foliage leaves for a Drepanos-

Maximum

diameter:

tachyum. It is somewhat

Minimum

temperature:

tolerant of drought

(Stapleton

1994d).

Drepanostachyum falcatum

2 in. (1.25 cm) 26°F

anum in marginal winter climates.

(—3°C)

Light: partial shade Heavily browsed, Drepanostachyum falcatum is seldom found in an unpillaged state in its natural habitats. Although the culms are not very straight and have somewhat swollen nodes, they are often used for basket weaving.

Drepanostachyum khasianum Maximum

height:

Maximum

diameter:

Minimum

temperature:

16 ft. (5 m) '% in. (1.25 em) 22°F

(-6°C)

Light: partial shade In its natural environment, Drepanostachyunt khasianum is heavily browsed and is most often encountered as a scruffy scrub plant less than 10 ft. (3 m) tall. Protected, it is an attractive, somewhat

tender, mountain

bamboo.

Although the name has been misapplied to other species, the plants in general circulation in the United States appear to be correctly named. The American variants, however,

have

larger leaves and are apparently less hardy than examples of the species observed elsewhere.

Drepanostachyum sengteeanum Maximum

height:

Maximum

diameter:

Minimum

temperature:

16 ft. (5 m) 4 in. (1.25 cm) 20°F

hardier than D. khasi-

(—7°C)

Light: partial shade This bamboo is in distribution in the United

Fargesia Most pachymorph

bamboos are semitropical or

tropical, with little cold tolerance, but some species of Fargesia, a genus of pachymorph bamboos, are among the most cold hardy of all bamboos. Both F. nitida and F. murielae, for example, reportedly can withstand temperature drops to -20°F (~29°C) without leaf damage. These species have been growing successfully in Norway for more than 30 years, and F. nitida has survived winters as far north as Tromso, Norway, at nearly 70°N latitude, well into the Arctic Circle (Flatabo

1995). It should be noted

that the concept of cold tolerance is relative. Although foliage damage has become a standard indicator of winter hardiness, some bamboos in their native environments are naturally deciduous in winter, putting on a flush growth of foliage in the spring. The genus Fargesia was once thought to be a small one, comprising perhaps three species, but Chinese research has brought the total to approximately 80 species. However, some of those recently identified are now known to belong in the newly identified genus Borinda. The towering mountains and terrain of central China create isolated pockets and unique environments, such that the entire population of some species may exist on a single mountain,

or even on a single mountain slope.

Fargesia Fargesias range in size from small plants about 5 ft. (1.5 m) tall, to much larger plants up to 27 ft. (8 m) tall and.2 in. (5 cm) in diameter. In general, particularly with respect to the species cultivated in the West, the plants exhibit a typical montane bamboo form, with nu-

merous branches and delicate leaves on slender arching culms—more bushlike than arborescent. Befitting their hardiness, the leaves are prominently tessellated. Although many species are exceptionally cold tolerant, most fargesias, like other Old World montane bamboos, do not thrive in strong sunlight, high temperatures, warm soils, or drought conditions. In a landscape or other controlled environment, shade and water can be provided, but ensuring moderate summer temperatures is more of a problem. Most fargesias are not the best choice in climates where the severe cold temperatures of winter are matched by the intense heat of summer. As

usual, there are exceptions. Some clones of F

nitida are reportedly more heat tolerant.

Fargesia adpressa

Maximum height: 18 ft. (5.5 m)

Maximum

diameter:

114 in. (3.2 cm)

Minimum

temperature: 0°F (—18°C)

Light: partial shade The culm leaf of Fargesia adpressa is shorter than the internode and not readily deciduous. In its native China, this species does not shoot until midsummer. In the United States, at least some the material in circulation as F. adpressa is

probably misidentified, and is likely F murielae or another Fargesia species.

Fargesia angustissima Maximum

height: 23 ft. (7 m)

Maximum

diameter:

4 in. (2 cm)

Minimum temperature:

15°F (-9°C)

Light: partial shade Native to the evergreen, broad-leaved forests of Sichuan, Fargesia angustissima is used for weaving and provides food for the giant panda.

New shoots are purple to purple-green. The young culms are heavily covered with white powder. Some species that were formerly placed in Fargesia have been moved to the new genus Borinda. Fargesia angustissima is probably a species of Borinda, although as of this writing, a change has not yet been made.

Fargesia dracocephala Common

name: dragon’s head bamboo

Maximum

height:

16 ft. (5 m)

Maximum

diameter:

Minimum

temperature:

% in. (2 cm) —10°F

(—23°C)

Light: partial shade Fargesia dracocephala is one of the bamboos that provide food for the giant panda in its native China, and it is also a highly attractive ornamental. When exposed to the sun, the culms may turn red or reddish black. The dense, dark green foliage leaves do not curl in the sun and heat like many others of the genus. This species appears to be less vigorous, however, and slower to develop significant size. Many of the plants in circulation have been propagated from seedlings grown in the late 1980s or early 1990s. The numerous seedlings have resulted in plants with slightly different culm coloration and growth habit.

Fargesia murielae

Common synonyms: Sinarundinaria murielae, Thamnocalamus spathaceus Common name: umbrella bamboo Maximum

height:

Maximum

diameter:

15 ft. (4.5 m)

Minimum

temperature: —20°F

/2 in. (1.25 cm) (—29°C)

Light: full shade Fargesia murielae is one of the world’s most

winter hardy bamboos. Its green culms bear masses of delicate pea-green leaves. In a clump, the upper portion of the culms arch in a manner reminiscent of an umbrella’s shape, thus its common name, umbrella bamboo. A choice ornamental, F. murielae needs some

287

4

é é

Chapter

9: Bamboo Genera, Species, and Cultivars

shade, and a wide space to display its airy, arching mass of foliage. It grows at elevations of up to 10,000 ft. (3000 m) in China and is a

food source for the giant panda. China’s Hubei Province in 1907 British plant collector Ernest H. bamboo is named alter Wilson’s Muriel.

Collected in by the famous Wilson, the daughter,

synonyms:

Fargesia spathacea,

Sinarundinaria nitida Common name: blue fountain bamboo Maximum

height:

Maximum

diameter:

Minimum

temperature: —20°F (—29°C)

12 ft. (4 m) ' in. (1.25 cm)

Light: full shade Along with Fargesia murielae, F. nitida is one

of the world’s most winter hardy bamboos, and a choice ornamental. The dark red-purple or dark brown-purple of the culms becomes more pronounced with some sun exposure, setting off the masses of delicate dark green leaves. Young culms are coated with a blue-white waxy powder. New shoots are branchless in the first season, branching in the second year. The culms are more upright than those of F. murielae, giving the

clump more of a fountain

shape than an umbrella shape. The shape and the blue-white coating on the new culms give e to the plant’s common tain bamboo.

Fargesia nitida ‘De Belder’

Maximum height: 10 ft. (3 m) Maximum diameter: 2 in. (1.25 cm) Minimum

Fargesia nitida Common

Although its leaves curl more readily in the sun, it is reportedly more heat tolerant than other F nitida clones. It may be slightly less cold tolerant.

name, blue foun-

Fargesia nitida has a number of

cultivars that differ more or less distinctly according to growing conditions. In China, this species is one of the food plants for the giant

panda.

Fargesia nitida ‘Anceps’

temperature:

—20°F

(-29°C)

Light: full shade Possessing the dark red-purple or dark brown-purple culm coloration of the type form, this cultivar of Fargesia nitida is reportedly shorter, but more rapidly spreading, with culms that bend outward at their base before becoming vertical. Fargesia nitida ‘De Belder’ forms a foliage canopy of short, dark green leaves, which curl less in the sun than those of the principal form.

Fargesia nitida ‘Eisenach’ Maximum

height: 14 ft. (4.2 m)

Maximum

diameter:

Minimum

temperature: —20°F (—29°C)

2 in. (1.25 cm)

Light: full shade Fargesia nitida ‘Eisenach’ has the dark red-

purple or dark brown-purple culm coloration of the type form, but it has smaller dark green leaves, a more arching habit, and culms that tend to bifurcate at their base. In parts of Europe, this cultivar grows taller than the type form. In parts of the eastern United States, it grows significantly less tall, possibly suggesting a greater sensitivity to growing conditions.

Fargesia nitida ‘Ems River’ Maximum

height: 14 ft. (4.2 m)

Maximum

diameter:

Maximum

height: 12 ft. (4 m)

Minimum

temperature: —20°F

Maximum

diameter:

Minimum

temperature: —20°F (-29°C)

Light: full shade Fargesia nitida ‘Ems River’ is reportedly among the more upright of the numerous cultivars. The bamboos in circulation under this name may in fact be multiple cultivars, rather than plants of the same cultivar. Reported

2 in. (1.25 cm)

Light: full shade Longer leaves, less pronounced culm coloration, and a more open growth habit are characteristics of the Fargesia nitida cultivar ‘Anceps’.

2 in. (1.25 cm) (-29°C)

Fargesia nitida.

Author's garden

290

Chapter 9: Bamboo Genera, Species, and Cultivars characteristics are inconsistent. The leaves, for example, are reportedly both smaller and larger than the type form.

Fargesia nitida ‘McClure’ Maximum

height:

18 ft. (5.5 m)

Maximum

diameter:

Minimum

temperature: —20°F (-29°C)

2 in. (1.25 cm)

Light: full shade This bamboo once grew in the private garden of the renowned bamboo researcher F. A. McClure, after whom the cultivar is named. It is the largest of the F. nitida cultivars, has longer leaves and branches than the type form, and develops a weeping habit. Because of its size, vigor, and growth habit, ‘McClure’ requires more space than other cultivars, and it can sometimes look a bit unkempt in comparison.

Fargesia nitida ‘Nymphenburg’ Maximum

height: 12 ft. (4 m)

Maximum

diameter: 2 in. (1.25 cm)

Minimum

temperature:

—20°F

(—29°C)

Light: full shade Because of its long narrow leaves, nitida ‘Nymphenburg’ is reminiscent of the delicate Himalayan mountain but it is far hardier. It lacks the hairs

Fargesia of some bamboos, on the

culm leaf sheaths that are typical of the type

form and the other cultivars. Regarded as an outstanding specimen plant, ‘Nymphenburg’ along with ‘Anceps; looks and grows best in somewhat

shadier locations.

Fargesia robusta Maximum

height: 20 ft. (6 m)

Maximum

diameter:

Minimum

temperature: 0°F (—18°C)

| in. (2.5 cm)

Light: partial shade Among the larger and more vigorous of the genus, Fargesia robusta is used for weaving and walking sticks in its native China, and the shoots are harvested for the table. It is also a major food source for the giant panda.

Fargesia utilis Maximum

height:

15 ft. (4.5 m)

Maximum

diameter:

% in. (2 cm)

Minimum temperature: 0°F (-18°C) Light: mostly sunny An excellent ornamental, Fargesia utilis grows in a tight clump, with small, delicate leaves supported by culms and branches that turn burgundy red in the sun. Leaf tessellation is relatively indistinct. In China, shooting occurs in August. The shoots are edible.

Gigantochloa

Native to Asia and the Pacific Islands, Gigantochloa is a genus of giant, clumping, tropical bamboos that generally resemble Bambusa. Unlike many other tropical bamboos, Gigantochloa is generally not monocarpic, but may partially flower on an irregular basis, creating more frequent opportunity for hybridization. On the other hand, only six Gigantochloa species are known to have produced viable seed, and many of today’s Gigantochloa may be sterile hybrids. It has been suggested that many of the Gigantochloa forms in cultivation in Indonesia today are the result of selection, cultivation, and vegetative propagation of elite hybrid forms dating back to the Proto-Malays thousands of years ago. Over many millennia, the selection process may have excluded bamboo strains with gregarious flowering cycles that would threaten the demise of the stand, or

perhaps, it may have excluded bamboos with flowering of any kind. Gigantochloa apus and G. levis have not readily hybridized, but other species, such as G. atroviolacea and, particularly, G. atter, have multiple hybrid forms. There are some 37 known species, but it has been estimated that there may be as many as 200 Gigantochloa forms. Further investigations of these forms likely will show that some should be accorded species status (Muller 1996a).

Some of the cultivated Gigantochloa are

Gigantochloa

reportedly less starchy than Bambusa, and thus are far more resistant to attack by beetles and fungus. Gigantochloa propagates easily by division or from single-node culm cuttings. The International Network for Bamboo and Rattan

and subsequently established in other New World locations, including Puerto Rico and

(INBAR),

in cooperation

with the Interna-

Nicaragua.

Gigantochloa atroviolacea Maximum

height: 55 ft. (17 m)

tional Plant Genetic Resources Institute, devel-

Maximum

diameter: 4 in. (10 cm)

oped a list of priority bamboos that merited focused research and wider use. Although the listing and choices are somewhat controversial, itis nonetheless notable that the original list of 19 species included 3 Gigantochloa: G. apus, G

Minimum

temperature: 28°F (—2°C)

levis, and G. pseudoarundinacea

Gigantochloa albociliata Common liata

synonym: Pseudoxytenanthera alboci-

Maximum

height:

Maximum

diameter:

Minimum

temperature:

Light: full sun Gigantochloa atroviolacea is a highly attractive ornamental

bamboo

from Java and Sumatra.

The young culms are initially dark green, turning rapidly to deep brown-black or deep purple-black. The deciduous culm leaves ensure that the attractive culms are visually unencumbered. Lower nodes may have aerial roots. The cured culms retain their black color and

30 ft. (9 m) 1 in. (2.5 cm) 30°F (—1°C)

Light: full sun Gigantochloa albociliata flowers weakly almost every year, but does not produce viable

seed. The green culms are covered with white, stiff hairs and are bending, not strongly upright. The shoots are edible, and the species is cultivated commercially in Thailand. Some authorities place this species in the genus Pseudoxytenanthera.

Gigantochloa apus Maximum

height: 65 ft. (20 m)

Maximum

diameter: 4 in. (10 cm)

Minimum

temperature: 27°F (—3°C)

Light: full sun Native to Java, Gigantochloa apus is an exceptionally strong bamboo, both as a whole culm and split for woven work. The strong culms taper very little and are used for roof rafters. The bitter shoots are buried in the mud for several days before being cooked and eaten. The leaves are up to 15 in. (38 cm) long and 2% in.

(6.3 cm) wide. Gigantochloa apus was introduced into the United States in about 1932,

Gigantochloa atroviolacea. Quail Botanical Gardens.

291

292

Chapter

9:

Bamboo

Genera,

Species,

and

Cultivars

tion, musical instruments, and other craft

United States and other parts of the New World as Gigantochloa verticillata. Many different spe-

items. The shoots are edible. This species is

cies in the genus have been erroneously

often mistaken

are used for building and furniture construc-

in-

closely

resembles. The culms of B. lako have

cluded under that name. Gigantochloa pseudoarundinacea is one that is now separated from

a shiny

surface, however,

the cluster and given its own

for Bambusa lako, which

it

whereas those of

identity. It has

G. atroviolacea have more of a matt finish.

likely been in cultivation

Gigantochloa atter

years, and reportedly there are a number of cultivars with distinct characteristics. All have

Maximum

height: 72 ft. (22 m)

striped culms. Although

Maximum

diameter: 6 in.

tallest timber bamboos,

Minimum

temperature:

(15 cm)

forms that may

This giant bamboo importance.

among

the

G. pseudoarundinacea height.

is of significant economic

Its culms are strong, straight, and

easily worked,

its large shoots reportedly taste

excellent, and the species is regarded as an outstanding candidate for the production of paper

one day be accorded species only

potentially

seldom approaches its maximum

28°F (—2°C)

Light: full sun Long cultivated in Indonesia by indigenous peoples, Gigantochloa atter has many related status. Known

for thousands of

in cultivation, the species

has no recorded flowering. It is speculated that

pulp. In addition to its utility,

selection by indigenous peoples over

doarundinacea is a very attractive ornamental.

the mil-

lennia has resulted in forms that exist only

in a

vegetative state, and thus do not threaten the demise of the resource with gregarious flower-

ing cycles. The productive clumps of G. atter yield many exceptional

tasting shoots.

The

culms are straight and strong, and the wood

is

used in construction and for musical instru-

ments and other handicraft.

Gigantochloa hasskarliana Maximum

height: 30 ft. (9 m)

Maximum

diameter: 22 in. (6.3 cm)

Minimum

temperature: 28°F (-2°C)

Light: full sun Native to Java, Gigantochloa hasskarliana is

planted as a hedge and is used for weaving and basket making. It is fast growing and vigorous, rapidly forming a dense clump.

Gigantochloa pseudoarundinacea

Common synonym: Gigantochloa verticillata Maximum height: 100 ft. (30 m) Maximum

diameter:

5 in.

(13 cm)

Minimum

temperature: 28°F (—2°C)

Light: full sun This bamboo

was introduced into the

Gigantochloa pseudoarundinacea. Quail Botanical Gardens.

Gigantochloa pseu-

Gigantochloa

Gigantochloa wrayi Maximum

height: 34 ft. (10 m)

Maximum

diameter:

Minimum

temperature:

3 ins (7.5 cm) 30°F (—1°C)

Light: full sun Distributed in peninsular Malaysia and peninsular Thailand, Gigantochloa wrayi is an attractive bamboo with long internodes. The split culms are used for making baskets.

Guadua Most New World bamboos are relatively small, but some species of Guadua rival the largest of the Old World bamboos. A New World tropical bamboo, Guadua was once classified as a subgenus of Bambusa, but is now recognized as a

monly termed “clumping bamboos” because of their generally clumping habit, but some species of Guadua are hardly clumping. The longnecked rhizomes of certain species may extend some 20 ft. (6 m) or more before turning upward into a new culm, easily outdistancing many “running” bamboos with leptomorph rhizome systems. Rather than “clumping” bamboo, Guadua bamboos are more properly characterized as having a pachymorph rhizome system and a diffuse habit—though even this rather understates the matter.

Guadua amplexifolia Maximum

height: 60 ft. (18 m)

Maximum

diameter:

distinct genus. Guadua consists of approxi-

Minimum

temperature:

mately 24 described species and a few more undescribed species, ranging from various vining types to the giant Guadua, for which the genus is noted. Unlike some Bambusa, Guadua bamboos are intolerant of any cold. Guadua generally has thorny basal branches. The inter-

Light: full sun Guadua amplexifolia has a more pronounced

4 in. (10 cm) 30°F

(—1°C)

arching habit than other large Guadua species.

Typically thorny, it may be thornless in the more northerly reaches of its range. The lower culm leaves are persistent, but upper culm

nodes may contain water, suggesting that the

leaves are rapidly deciduous.

water may be stored and reused during dry periods. The culm leaves are deciduous (Judzie-

Guadua angustifolia

wicz etal. 1999).

Maximum

height: 100 ft. (30 m)

Maximum

diameter:

sea level to 7200 ft. (2200 m), from Mexico

Minimum

temperature:

through Uruguay and Argentina, excluding Chile. The name Guadua is a Latinized version of the name given to these bamboos by the indigenous peoples of Ecuador and Colombia. The genus comprises the most extensive bamboo forests of any New World bamboo, covering vast areas of up to 47,000 square miles (122,000 square kilometers) in the Brazilian Amazon and Peru alone (Londono 1996). Much more is now known about the genus as a result of the work of Ximena Londono, the current authority on the genus. The rhizome structure and growth habit of Guadua reveals the limitations and occasional inadequacy of common terminology. Bamboos with pachymorph rhizome systems are com-

Light: full sun

The natural habitat of Guadua ranges from

9 in. (22 cm) 30°F

(—1°C)

The type species of the genus, Guadua angustifolia is the largest of all the New World bam-

boos. Native to northeastern South America, it is prominent in Colombia and Ecuador, where it is known, respectively, as guadua and cana brava. China has its remarkable moso forests; South America has its guaduales, expanses of land dominated by species of Guadua, prominent among them G. angustifolia. The species thrives ina fairly broad elevation range, from sea level to 5900 ft. (1800 m). It grows best within a temperature range of 63 to 75°F (17 to 24°C)—

clearly not a bamboo that thrives on frosty conditions. Nor is ita bamboo for dry conditions, thriving in natural habitats with an annual pre-

293

294

Chapter

9: Bamboo Genera, Species, and Cultivars

cipitation ranging from 80 to 240 in. 6000 mm) a year

(Judziewicz et al.

(2000 to 1999).

Guadua angustifolia has outstanding me-

gustifolia, the only New World bamboo on the original list of 19 species. The list and criteria are somewhat controversial, and the paucity of

chanical properties. Very strong and easily

New

workable, it is used in construction of modest homes by indigenous peoples, as well as in multimillion-dollar architectural masterpieces. Most tropical bamboos are chronically subject

familiarity with the breadth and depth of New

Guadua angustifolia var. bicolor

to insect

Maximum

height:

Maximum

diameter:

when

attack and

rot, but G.

untreated, is highly

angustifolia, even

resistant. Docu-

mented accounts have demonstrated that its longevity is greater than that of hardwoods used alongside it (McClure

World bamboos.

Minimum

100 ft.

(30 m)

8 in. (20 cm)

temperature:

30°F

(—1°C)

Light: full sun

Similar to the principal form, but the culms

1966)

The list of priority bamboos compiled by the International Network

World species on the list suggests a lack of

for Bamboo and Rattan,

in cooperation with the International Plant Genetic Resources Institute, included Guadua an-

have

yellow and green striping.

Guadua angustifolia ‘Less Thorny’ Maximum Maximum

height: 100 ft. (30 m) diameter: 8 in. (20 cm)

Minimum

temperature:

30°F (—1°C)

Light: full sun Similar

to the type form, but the culms have

fewer and smaller thorns.

Guadua chacoensis Maximum

height: 60 ft. (18 m)

Maximum

diameter: 6 in. (15 cm)

Minimum

temperature:

30°F

(

G)

Light: full sun Sometimes mistaken the thorny

for Guadua angustifolia,

G. chacoensis is native to northern

Argentina and southern Paraguay. Its culms are used

in construction.

Guadua velutina Maximum

height: 60 ft.

Maximum

diameter: 4 in. (10 cm)

Minimum temperature: Light: full sun

*

q

y

Guadua angustifolia. Quail Botanical Gardens.

(18 m) 28°F (—2°C)

Guadua velutina has the northernmost distribution of the genus, extending into Mexico, from Tamaulipas to Oaxaca. The culms are thick walled and are used in construction. The species epithet references the velvety pubescence on the spikelets (Lynn Clark, personal communication).

Hibanobambusa

Hibanobambusa The name

striped leaves. When

Hibanobambusa

means bamboo

growing on Mt. Hiba. This single-species genus

reportedly originated in the wild from a crossing of Sasa veitchii {. tyugokensis and Phyllostachys

nigra var. henonis sometime around the end of the 19th century or beginning of the 20th century. Hibanobambusa has a leptomorph rhi-

grown

in strong sun,

some of the leaves may have purple tones in the variegation.

Himalayacalamus

Himalayacalamus is a genus of marginally hardy, pachymorph, montane bamboos that

grow up to 26 ft. (8 m) tall. Species are found

zome system and characteristics that suggest its

at elevations of 6100 to 9200 ft. (1850 to 2800

alleged parents. The culm leaves are deciduous, as with Phyllostachys, but each node generally bears only one branch (or occasionally two

m) in the cool, broad-leaved forests of the Himalayas. Slender culms, profuse with fine branches and delicate leaves, are the hallmark of these attractive bamboos. Two additional

or three branches after the first year). Hibano-

bambusa flowered in the early 1970s, but apparently few seeds were produced and none

species from Nepal are just now coming into

proved viable. The flowers are reportedly simi-

cultivation, H. porcatus and H. cupreus Unlike in truly hardy bamboos, the leaf

lar to those of Phyllostachys, but they usually

veins are not prominently tessellated in Hima-

have six stamens, as in Sasa.

Doubt

remains as

to whether the genus is the hybrid that has

been suggested. Studies using molecular techniques could help re eal more about the origins of the genus

(Lynn Clark, personal com-

munication).

Hibanobambusa tranquillans Maximum

height:

16 ft. (5 m)

Maximum

diameter:

Minimum

temperature: O°F (-18°C)

iS

in. (3.2 cm)

Light: mostly sunny Sharing some of the overt characteristics of its alleged parents, Hibanobambusa tranquillans has the larger leaves of a Sasa, up to 10 in. (25 cm) long and 14 in. (3.2 cm) wide, and the deciduous culm leaves characteristic of Phyllostachys

Hibanobambusa tranquillans ‘Shiroshima’ Maximum

height: 16 ft. (5 m)

Maximum

diameter:

14 in. (3.2 cm)

Minimum temperature: 0°F (-18°C) Light: mostly sunny A very attractive ornamental, Hibanobambusa tranquillans ‘Shiroshima’ is similar to the type form, but with strongly variegated, white-

Hibanobambusa

Author's garden.

tranquillans ‘Shiroshima’.

295

296

Chapter 9: Bamboo Genera, Species, and Cultivars

layacalamus. This genus can be distinguished from the similar-looking Thanimocalamus by the absence of prominent leaf tessellation. In the first year of culm growth, each node has about 15 branches. In subsequent years, a node may have up to 40 branches. Himalayacalamus plants are useful as forage, pasture for animals, and as weaving material. The new shoots of many spe-

cies are excellent for the table (Stapleton 1994d). Considerable confusion surrounds the identity and classification of many of the pachymorph

montane bamboos.

As early as 1896,

in The Bamboo Garden, A. B. Freeman-Mitford

refers to a history of confusion and widespread misidentification. The identity problem is most acute between

Himalayacalamus

and

Drepanos-

tachyum. Not only are the genera frequently confused, but also some of the species have been mistakenly interchangeably labeled in

Himalayacalamus asper Maximum

height: 20 ft. (6 m)

Maximum

diameter:

Minimum

temperature:

% in. (2 cm)

15°F (-9°C)

Light: partial shade Indigenous to Nepal, at elevations ranging from 6000 to 7500 ft. (1800 to 2300 m), Hima-

layacalamus asper is generally similar to H. falconeri, but the surface of H. asper culm leaf sheaths is rough or slightly hairy. The culms have a drooping habit. Flexible, they are often used for weaving, although when available, other Himalayacalamus species with longer internodes are used in preference. In the United States, the bamboos in the garden trade that were grown under the name of Neomicrocalamus microphyllus are actually H. asper (Stapleton 1994c, 1994e,

personal communication).

the nursery trade, exacerbating and perpetuat-

Himalayacalamus falconeri

ing the problem. In the case of H. falconeri and

Maximum

height: 25 ft. (7.5 m)

D. falcatum, the source of confusion rests as

Maximum

diameter:

much

top, Himalayacalamus is smooth. Drepanostach-

Minimum temperature: 15°F Light: partial shade In its native environment, falconeri is found at relatively ranging from 6600 to 8200 ft.

yumi is rough. Himalayacalamus branches differ

m). The shoots are edible and can be found

from Drepanostachyum in that they vary in size,

for sale in the markets of Katmandu. The relatively large, flexible culms make excellent weaving material. Cultivated plants came to the United States from northwest India in the 19th century. Unfortunately, some or all of the plants in distribution under the names H. fal-

with the similarity of the names as with

the similarity between the species. Several features distinguish the two genera. On the inside of the culm leaf sheaths, near the

grow more erect, and are not arrayed as broadly around the circumference of the culm. In its natural environment, Himalayacalamus is generally found at higher elevations than Drepanostachyum, and it is more cold tolerant. Drepanostachyum, however, is more tolerant of drought. The culms of some Himalayacalamus species are slightly larger, reaching 1% in. (3.5 cm), versus a maximum

of 1

in. (2.5 cm)

tachyum (Stapleton

for Drepanos-

1994d).

1% in. (3.5 cm)

(-9°C) Himalayacalamus high elevations, (2000 to 2500

coneri and Arundinaria falconeri in the United

States, and perhaps elsewhere, are a different species, the newly named Drepanostachyum sengteeanum (Chris Stapleton, personal communication).

Unlike many bamboos, at least some Himalayacalamus species require a period of dormancy before their seed will germinate. Ata

Himalayacalamus falconeri‘Damarapa’

hookerianus reportedly requires one to eight

Common synonym: Drepanostachyum hookerianum Maximum height: 25 ft. (7.5 m)

months before germination occurs.

Maximum

temperature

of 68 to 77°F

(20 to 25°C),

H.

diameter:

1% in. (3.5 em)

s

Himalayacalamus asper. Bamboo Sourcery.

298

Chapter 9: Bamboo Genera, Species, and Cultivars

Minimum

temperature:

15°F (—9°C)

Light: partial shade Often found in the trade under the name Drepanostachyum hookerianum,

Himalayacalamus

falconeri ‘Damarapa’ is a striking plant, displaying culms with green and yellow stripes that change to lavender, red, and pink tones, depending on exposure to the sun and cool air.

Himalayacalamus hookerianus Common

synonyms: Arundinaria hookeriana,

Sinarundinaria hookeriana Maximum

height: 23 ft. (7 m)

Maximum

diameter:

Minimum

temperature:

1%

in. (3.2 cm)

15°F (—9°C)

Light: partial shade This species is an exceptionally attractive bamboo. The new culms are a striking blue color, complemented by a profusion of small, delicate leaves. In subsequent years, the culm coloration ranges from yellow-green to purplered. The lower nodes are free of branches, and the internodes are long, contributing to the desirability of the culms for weaving. In its natural environment, Himalayacalamus hookerianus is an

understory plant. Sheltered by the forest canopy that mitigates the harshness of wind and cold, it can prosper in spite of its marginal hardiness.

Named after Sir Joseph Hooker, who found the bamboo

in flower in 1848 on an approach

the culm where nodes may have up to three branches). Unlike Sasa, the supranodal ridges are unswollen, and the leaves typically have a greater length to width ratio—a length of over four or more times their width in Indocalamus, but frequently less than four times their width in Sasa. Also unlike Sasa, Indocalamus suffers little from withering of the leaf tips or margins, thus sometimes offering a brighter, fresher look. Indocalamus culm leaf sheaths are persistent and usually shorter than the internodes. The diameter of the branches is nearly the same as the diameter of the culm. The approximately 35 known species of Indocalamus have leptomorph rhizome systems and a strongly running habit. Most prefer some shade and are cold hardy.

Indocalamus latifolius Maximum

height:

10 ft. (3 m)

Maximum

diameter:

¥% in. (1 cm)

Minimum temperature: 0°F (—18°C) Light: full shade Native to central and eastern China, Indocalamus latifolius culms are used for making chopsticks, brushes, and pens. The leaves are up to 15 in. (38 cm) long and 3 in. (7.5 cm) wide, and are used to make mats, the lining of hats, or for wrapping food. In the landscape, it makes a large attractive bush.

to a mountain pass in Sikkim, Himalayacalamus hookerianus has probably suffered more no-

Indocalamus longiauritus Maximum

height: 10 ft. (3 m)

menclature abuse than any other bamboo.

Maximum

diameter: ¥% in. (1 cm)

Minimum

temperature: 0°F (—18°C)

Be-

sides the species being incorrectly associated

with several other genera, at least two other bamboos are commonly labeled and traded with variants of the name “hookerianus,” including Drepanostachyum hookerianum, which, in itself, is a striking bamboo, now thought to be a cultivarof H. falconeri (Stapleton 1994f).

Indocalamus

Somewhat similar to Sasa, Indocalamus is a genus of broad-leaved bamboos with a single main branch per node (except near the top of

Light: partial shade Native to China, this species is attractive and more tolerant of sun than others of the genus. The large leaves of Indocalamus longiauritus are used to make mats, the lining of hats, or for wrapping food. The culms are used for making chopsticks, brushes, and pens.

Indocalamus tessellatus Maximum

height: 7 ft. (2.1 m)

Maximum

diameter:

¥% in. (1 cm)

Indocalamus tessellatus.

RKR Bamboo Plantation.

300

Chapter 9: Bamboo Genera, Species, and Minimum

temperature:

—5°F

Cultivars

(—21°C)

Light: full shade Indocalamus tessellatus leaves are up to 2 ft. (0.6 m) long and 4 in. (10 cm) wide, the largest

leaves of any temperate-climate bamboo. The large drooping leaves obscure the culms and branches, giving the plant more of amounded bush appearance than some of the other members of the genus. Despite the tropical look of its foliage, this species is very hardy, and it grows well in containers. Its large leaves are used for making mats and for wrapping food.

Lithachne A member of the Olyreae, a tribe of tropical, herbaceous, forest bamboos, Lithachne is somewhat more tolerant of occasional dryness and cool growing conditions than most other tropical, herbaceous genera. Consisting of four species, Lithachne is distributed from Mexico and the Caribbean to Paraguay and northern Argentina (Judziewicz et al. 1999). The base of Lithachne leaves are distinctively truncated and asymmetrically attached to the pseudopetiole. Lithachne foliage leaves fold downward

at night, beginning at sunset, pro-

gressing over a four-hour period, then revers-

ing the process at dawn. The plants flower throughout the year. Some species are considered weedy in their native habitats.

Lithachne humilis

Maximum height: 2 ft. (15 cm) Maximum diameter: “ie in. (0.2 em) Minimum

temperature:

32°F (0°C)

Light: partial shade Lithachne humilis flowers regularly throughout the year and produces viable seed without threatening the plant’s vigor. Its distinctive foliage leaves fold down at night. Lithachne humilis is more tolerant of cool, dry growing conditions than most herbaceous species. It is only moderately attractive, but its distinctive flowers are appealing and add interest, as does the folding of its leaves at night.

Neomicrocalamus

Neomicrocalamus is a genus of pachymorph bamboos from Bhutan, northeastern India, China, and Vietnam. It is generally found in wetter subtropical forests than Himalayacala-

mus and Drepanostachyum. As suggested by its untessellated leaf blades, Neomicrocalamus is not frost hardy. The culm internodes are long and shiny. Each node may bear up to 18 principal branches of similar size, or there may be dominant branches. The culm leaf blades are erect and needlelike. The plants often exhibit a scrambling, clambering habit, spreading and draping over small trees for support. The flexible culms are choice material for weaving. In the United States, the plants in the garden trade that were identified and marketed as Neomicrocalamus microphyllus are actually Hima-

layacalamus asper (Chris Stapleton, personal communication).

Neomicrocalamus andropogonifolius Maximum

height: 40 ft. (12 m)

Maximum

diameter:

Minimum

temperature:

| in. (2.5 cm) 26°F

(—3°C)

Light: partial shade Distributed in Bhutan, southeastern Tibet, and northeastern India, Neomicrocalamus andropogonifolius is a pachymorph bamboo, with rhizomes up to 6 [t. (1.8 m) long, forming very open clumps. It is an attractive clambering bamboo, with elegant curtains of shiny foliage cascading from its supports.

Olmeca Indigenous to southern Mexico, Olmeca is named after the Olmecs, an ancient civilization predating the Mayas. The genus consists of two species, O. recta and O. reflexa. These bamboos are prime examples of the breakdown in the terminology “clumping bamboo” when referring to any bamboo with a pachymorph rhizome system. While synonymizing the terms may work moderately well for many bamboos grown in the garden, it certainly does not work

Pa cS o Be) G

Lv)

rr

a

s

) ie)

3

i

oO

fo cS g© s©

=

°

302

Chapter 9: Bamboo Genera, Species, and Cultivars

well for all bamboos. O/meca, for example, is characterized by exceptionally long rhizome necks that may extend up to 26 ft. (8 m) before turning upward to form a culm—hardly a clumping habit. The branching habit is also somewhat unusual. A single branch may form at each node, but then branch no further. Also relatively uncommon for bamboos, Olmeca produces fleshy fruits when it flowers.

Olmeca recta

Maximum

diameter:

% in. (2 cm)

Minimum temperature: 28°F (—2°C) Light: full sun Otatea acuminata ssp. acuminata is noted for its slender arching culms covered with delicate, feathery masses of leaves. Native to the hot lowlands of Mexico, and among the earliest cultivated New World bamboos, this species is used to make baskets, corrals, furniture, and toys. It is also incorporated into the walls, doors, and ceilings of buildings. Otatea acuminata ssp. acuminata is particularly desirable as

Maximum

height: 45 ft. (14 m)

roofing material, since it is more resistant than

Maximum

diameter:

other bamboos to rot, fungi, and insects.

Minimum

temperature:

2 in. (5 cm) 32°F (0°C)

Otatea acuminata ssp. aztecorum

Light: mostly sunny Olmeca recta is indigenous to the wet lowland forests of southern Mexico, at elevations

Common Maximum

height: 20 ft. (6 m)

from sea level to 2600

Maximum

diameter:

Minimum

temperature: 22°F (-6°C)

ft (800 m). The culms

are hollow and thin walled, covered by hard, persistent culm leaves. Branching begins at about

10 ft (3 m) above the ground,

and

the

foliage leaves have very short pseudopetioles, giving a palmlike appearance. In its native environment, O. recta forms dense stands known locally as jimbales.

Otatea A New World genus of subtropical or tropical pachymorph bamboos, Otatea consists of two known

species

(Judziewicz et al.

1999).

It is

more drought resistant than most New World bamboos, and its habitat includes seasonally dry areas along the Pacific Coast of Mexico and Central America, where the bamboos share their territory with cacti and agaves. Given the limestone soils typical of their habitat, otateas prefer less acidic soils than most bamboos. The genus name is a derivative of “otate, the name used by the Nahuatl Indians of central Mexico.

Otatea acuminata ssp. acuminata Common Maximum

synonym: height:

Ofatea acuminata 15 ft. (4.5 m)

name: Mexican 1

weeping in. (4 cm)

Light: mostly sunny Otatea acuminata ssp. aztecorum is larger than O. acuminata ssp. acuminata, and its masses of

leaves nearly obscure the culms. It is a pachymorph bamboo, but its rhizome necks are long, and the culms are spaced up to 2 ft. (0.6 m) apart.

Otatea fimbriata

Maximum height: 14 ft. (4.2 m) Maximum diameter: 4 in. (2 cm) Minimum

temperature: 24°F (—4°C)

Light: mostly sunny Otatea fimbriata has larger leaves than the other members of the genus, measuring up to 12 in. (30 cm) long and % in. (2 em) wide.

Oxytenanthera Oxytenanthera is a genus of tropical bamboos with pachymorph rhizome systems. The scope of the genus is currently a matter of discussion, ranging in inclusion from a monotypic genus exclusive to tropical Africa, to a wider ranging genus including species from the Asia-Pacific. The more narrow delineation of the genus

Otatea acuminata ssp. aztecorum, in flower and setting seed. Quail Botanical Gardens.

o

ae a )

Z

o

s

8 ao

5©

oO

3

He

© Es}

o

g>

fe)

Oxytenanthera

places previously included species in Dendrocalamus, Gigantochloa, and Pseudoxytenanthera.

Oxytenanthera abyssinica Maximum

height: 30 ft. (9 m)

Maximum

diameter: 4 in. (10 cm)

Minimum

temperature:

30°F (—1°C)

Light: full sun Oxytenanthera abyssinica is distributed throughout tropical Africa at elevations ranging from near sea level to 6600 ft. (2000 m), in

savannas and on hillsides. It prefers moist conditions along waterways, but it is also drought resistant, though it may become deciduous in hot, dry conditions. The new shoots are bluegreen, with cream-yellow leaf blades. Oxytenanthera abyssinica has been introduced into India as a source of pulp for paper, and it reportedly produces high yields of somewhat inferior pulp.

Phyllostachys Phyllostachys is a large genus of approximately 75 species and more than 200 varieties and forms. The species are widely distributed in the wild, in the temperate and semitropical areas of eastern Asia, from sea level up to 12,000 ft. (3700 m). Phyllostachys is the most northerly of all the giant arborescent bamboos. Eastern China appears to be the center of distribution. As with many species that have long been cultivated, the original, natural pattern of distribution of Phyllostachys is unclear, and some distribution is likely to have occurred via human migration in very early times. Nearly all P/ryllostachys species can be found in China, though P. humilis is an exception. Cultivated in Japan, P.

Common name: wine bamboo Maximum height: 30 ft. (9 m)

humilis sumed to have originated in China, but has not yet been recorded there. An impressive genus, Phyllostachys comprises many of the world’s most beautiful, and economically important, hardy bamboos. In China and Japan, it is the principal source of edible bamboo shoots, paper pulp, craftwork, and timber. In established forests, some species

Maximum

diameter: 4 in. (10 cm)

can reach a height of more than 90 ft. (27 m)

Minimum

temperature:

and a diameter of 7 in. (18 cm). Although

Oxytenanthera braunii

30°F (—1°C)

Light: full sun Some authorities regard Oxytenanthera braunii and O. abyssinica as synonymous, but at least some examples of O. braunii in cultivation, and from some indigenous regions, are distinctively

different. This, of course, raises the issue of whether they are correctly identified or are some other species altogether. For the moment, O. braunii is treated as a distinct species of Oxytenanthera. The growing shoots of Oxytenanthera braunii exude sap for many weeks after being topped. In Tanzania, they are topped at a height of roughly 3 ft. (about 1 m), and the sap is collected and fermented into a wine-like beverage

some Phyllostachys are huge plants with rapidly spreading leptomorph rhizomes, new rhizomes grow very close to the soil surface. As a result, the plant’s spread can be readily controlled with barriers or rhizome pruning more easily than other genera of leptomorph bamboos that may be much smaller, but have more rampant and deeper running rhizomes. Siebold and Zuccarini first described the genus in 1843, separating it from Bambusa.

bamboo. A single culm yields about 2/ gallons

They included only one species, Phyllostachys bambusoides, but suggested that “Bambusa nigra” might also belong in Phyllostachys. Bamboos of the genus Phyllostachys are readily identifiable by a pronounced sulcus (groove) that runs the length of the internode on the branching side. The branch buds, already

(10 liters) of sap. Reports of the drink’s merit

prominent, are pressed against the emerging

range from tasty to quite foul.

internode by the tightly wrapped culm leaf

called ulanzi, hence the common name wine

305

306

Chapter 9: Bamboo Genera, Species, and Cultivars

sheaths, creating the sulcus as the internode elongates. On a Phyllostachys culm, only the lowermost

internodes that emerge

from

branchless nodes are absent a sulcus. Some other bamboo genera, such as Semiarundinaria,

have a partial sulcus, but a pronounced sulcus running the full length of the internode is unique to Phyllostachys. It is, perhaps, the most readily identifiable bamboo genus. In some forms and cultivars, the sulcus is a different

color than the rest of the culm, typically yellow on a green culm or green on a

yellow culm.

Except for the lower nodes of older culms where the branch buds may remain dormant, branch development and emergence begins concurrently with the growth of the culm. The lowest nodes on the culm may have solitary

branches, but the typical branching pattern is two major, but unequally sized branches at each node. Occasionally, a third, much smaller branch may develop between the two principal branches. The culms and branches encompass a broad range of colors and surface finishes, including lime green, sulfur green, sulfur yellow, bluish green, chocolate, olive, straw yellow, green and yellow striped, shiny and waxy, velvety, matt finished, or white powdered. The coloration and patterns of Phyllostachys culm leaf sheaths are highly distinctive, and they are often an excellent means of readily identifying the species in the field. The culm

and branch leaves are immediately deciduous, dropping from the lower nodes, even as the upper internodes continue their extension. The immediately deciduous nature of Phyllostachys culm and branch leaves enhances their appeal in the landscape—not only is a scruffy look avoided, but the visual appeal is enhanced by immediate exposure of the bright fresh look of new culms and branches. Although, like virtually all bamboos, Phyllostachys is evergreen, it replaces its leaves gradually. The replacement is inconspicuous except

for the carpet of fallen leaves beneath the plant, which adds to the desirable layer of mulch. The principal leaf fall occurs in the spring. New leaves appear on new twigs, generated from lower buds on the existing twigs.

The leaves of Phyllostachys are lanceolate and distinctly tessellated. The lower leaves on a twig are somewhat shorter and broader, the upper leaves somewhat

longer and narrower.

A very young plant often has larger, sometimes much larger, leaves than an older plant of the same species. Older plants, with “normal,” smaller leaves and larger culms, begin to assume more of the arborescent stature and beauty for which this genus of giant, hardy, As seen on this new culm of Phyllostachys vivax, and characteristic of the genus, the culm leaves are

rapidly deciduous, clinging only briefly at the edge of the sheath base.

tree grasses is known.

Shoot initiation varies according to local conditions, but generally begins in March or April for early shooting species, through June

away, making way for A portion of the leaves of this Phyllostachys plant are withering and falling new branchlets.

308

Chapter 9: Bamboo Genera, Species, and Cultivars for late-shooting species. Some species, such as Phyllostachys aurea, exhibit a propensity for continued sporadic shooting throughout the growing season. Phyllostachys bissetii, P. heterc cla f. pubescens,

P. nuda, and

P. violascens are ex-

amples of early shooting species. Phyllostachys bambusoides and P. viridis are examples of lateshooting species. It is not uncommon for the culms of the earliest shooting species to have completed their vertical growth and be fully branched out before the latest species have even begun shooting. The difference in the time of shooting extends the length of bamboo’s most dramatic and interesting period, and it extends the season for harvesting shoots for the table. In 1913, using growth habit and inflorescence as criteria, Camus was the first to attempt a description of identifiable groups within the genus. Subsequent investigations employing morphological, biochemical, and molecular data have tended to support two sections within the genus, section Phyllostachys and section Heteroclada. Wang et al. (1980) pro-

posed these two sections, based on morphological characteristics. Except for differences in the sectional assignment of a few species, the sections and

their membership are supported by subsequent morphological information and by the DNA sequencing investigations of Renvoize and Hodkinson (1997). Wang et al. (1980) placed Phyl-

lostachys aureosulcata, P. nigra, and P. heterocycla in section Phyllostachys. Renvoize and Hodkinson place the three in section Heteroclada, based on their interpretation of morphological information

(DNA sequencing data were not avail-

able for these three species). Additional studies will likely produce adjustments in species membership

in the two sections, and perhaps

reveal additional sections of Phyllostachys, as the current two are not monophyletic.

Phyllostachys section Heteroclada

Characteristic of this section are culm leaf

blades at the tip of young shoots, forming a tight, erect bunch, and congested or glomerate (rounded,

tightly clustered mass) inflores-

cences. Some members of this section, and perhaps all, depending on the methods employed to determine section assignment, have rhizomes with air canals. The air canals are regarded as an adaptation to water-saturated soils. The type species for this section, Phyllostachys heteroclada, is commonly called water bamboo. Species in this section include P. atrovaginata, P. bissetii, P. heteroclada, P. humilis, P. incarnata, P. mannii, P. nidularia, P. parvifolia, and P. stimulosa.

Phyllostachys section Phyllostachys

Characteristic of this section are culm leaf blades at the tip of young shoots forming a loose bunch, and lax (loose and open, not tightly clustered) inflorescences. Species in this section include Phyllostachys acuta, P. angusta, P. arcana, P. aurea, P. bambusoides, P. dulcis, P. flexuosa, P. glauca, P. iridescens, P. makinoi, P. meyeri, P. nuda, P. platyglossa, P. praecox, P. propinqua, P. rubromarginata, P. viridiglaucescens, P. viridis,

and P. vivax.

Phyllostachys acuta Maximum

height: 28 ft. (8.5 m)

Maximum

diameter: 2/2 in. (6.3 cm)

Minimum

temperature:

0°F (—18°C)

Light: full sun This species was introduced into the United States from China’s Zhejiang Province in 1984. The young culms are dark green with purple nodes. With age, the culms turn lighter, to yellow-green. The shoots are harvested in China and are reportedly good tasting.

Phyllostachys angusta

Common name: stone bamboo (see text) Maximum

height: 25 ft. (7.5 m)

Maximum diameter: 12 in. (4 cm) Minimum

temperature: 0°F (—18°C)

Light: full sun

Phyllostachys

Introduced from Zhejiang Province into the United States in 1917 by plant explorer Frank Meyer, this bamboo has also been called by what was purportedly its Chinese name, Sah Chao

Chu, or stone bamboo.

(1989) indicates

that Meyer’s field notes were in error, and that Sah Chu was actually a name ascribed to Phyllo-

stachys nuda. The name “angusta” means narrow, referring to the culm leaf’s narrow sheath apex, ligule, and blade. The culms are straight with a narrow crown. In China, they are used for weaving, craftwork, and making fishing rods. The midseason shoots of this species are free of bitterness.

Phyllostachys arcana Maximum

height: 27 ft. (8 m)

Maximum

diameter:

1'

in. (4 cm)

Minimum temperature: 0°F (-18°C) Light: full sun The name Phyllostachys arcana has been variously attributed to the initial difficulty in establishing its distinguishing characteristics or, alternatively, to the supranodal ridge’s partial coverage of the dormant branch buds at the lower culm nodes. The internodes may develop an irregular pattern of black spots with age and exposure to sunlight. The nodes are rather prominent, and the size of the two main branches is more closely equal than is the case in most other species of Phyllostachys. In China,

Maximum

height: 30 ft. (9 m)

Maximum

diameter: 2% in. (7 cm)

Minimum

temperature: —5°F (-21°C)

Light: full sun In the United States, this bamboo was long known by the name Phyllostachys congesta, but is now thought to be properly termed P. atrovaginata. The culms taper rapidly, giving it a relatively large diameter in relation to its height. Phyllostachys atrovaginata is very useful in landscape settings where the substantial look of relatively large bamboo is desired, but not the height that typically accompanies the girth. The shoots of this species resemble those of Phyllostachys heteroclada and its forms, but can be distinguished by the absence of auricles and fimbriae from the culm leaf. Like P. heteroclada, it has air canals in the rhizomes and roots, an adaptation for growing in wet or boggy soils. The shoots are good tasting, and nearly free from bitterness even when raw. Phyllostachys atrovaginata is sometimes called incense bamboo because the surface of the culm has a scent that is said to resemble sandalwood. Rubbing your thumb and index finger along the internode of a young culm exposed to the sun releases the subtle but distinct fragrance.

Phyllostachys aurea

Common names: golden bamboo, fish-pole bamboo, hoteichiku

the culms of P. arcana are used for weaving and

Maximum

height: 27 ft. (8 m)

for handles on farm implements. The early season shoots are harvested for the table.

Maximum

diameter:

Minimum

temperature: 0°F (—18°C)

Phyllostachys arcana f. luteosulcata Maximum

height: 27 ft. (8 m)

Maximum diameter: 1 Minimum

in. (4 cm)

temperature: 0°F (-18°C)

Light: full sun Same as type form, but with yellow sulcus.

Phyllostachys atrovaginata Common Common

synonym: Phyllostachys congesta name: incense bamboo

1/4 in. (4.4 cm)

Light: full sun Also known as golden bamboo,

Phyllostachys

aurea is the most commonly cultivated bamboo in the United States. The new culms are green, not golden as the name suggests. Older culms that have been exposed to the sun take on more of a golden yellow color, providing the source of inspiration for the name. This was

likely the first species of Phyllostachys in America. Some reports place its introduction in the year 1882, in Alabama. Other reports cite an

309

310

Chapter 9: Bamboo Genera,

Species,

and Cultivars

even earlier introduction date of 1822, also in Alabama.

Phyllostachys aurea is distinguished by

its frequently compressed

internodes on the

lower portions of the culms.

The compressed

internodes provide a ready-made gripping

area, and the bamboo is used for walking sticks and umbrella handles in Asia. In the American South, the use of the culms as fishing poles has given it the name fish-pole bamboo. When a dense screen close to the ground is needed,

Phyllostachys aurea can be more effec-

tive than of nodes means a branches

other Phyllostachys, since the density on the lower portion of the culms also greater density of branches. The can also be pruned away to expose

the ornamental aspects of the compressed internodes. The culms are straight, stiffly erect, and do not strongly bend toward the light, as is the case with many other bamboos. The midseason shoots are relatively free from bitterness, even when

raw. Depending on growing

conditions, this species has a tendency for additional, sporadic shooting throughout the growing season Phyllostachys aurea is heat, cold, and drought tolerant, and it does well in a container and as a hedge. Most

Phyllostachys species grow poorly

in subtropical and tropical environments,

but

P. aurea is more tolerant than most, and it is even grown

commercially

furniture construction.

in Costa Rica for

Its reputation

for

spreading rapidly may be partially attributable to its ubiquity, and to the fact that most westerners are unfamiliar with managing bamboo’s growth

habits.

An excellent ornamental,

P.

aurea is sometimes ignored by collectors be-

cause it is so prevalent.

Phyllostachys aurea f. albo-variegata Maximum

height: 27 ft. (8 m)

Maximum

diameter:

Minimum

temperature:

1% in. (4.4 cm) 0°F

(—18°C)

Light: full sun The general characteristics

are the same as

Phyllostachys aurea. This is one of the few Phyllostachys with variegated leaves, and the white stripes give P. aurea {. albo-variegata a more deli-

cate look. Like all Phyllostachys bamboos, sun lover, but in hot, sunny

it is a

climates some

shading benefits the plant and the look of its leaves. Although it is an excellent ornamental, it receives less interest and attention than it would

if it were of a less common

species. Phyl-

lostachys aurea {. albo-variegata flowered gregariously in the United States in the late 1990s, >

~~

-

Phyllostachys aurea, showing the characteristic compressed internodes on the lower portion of the culm.

The branches are newly formed. Carol Giberson’s Garden.

placing it in jeopardy for many growers. As is usual for most variegated bamboo

forms and

cultivars, most seedlings lack variegation and merely show the characteristics of the principal form.

Phyllostachys

Phyllostachys aurea f. flavescensinversa Maximum

height: 27 ft. (8 m)

Maximum

diameter:

it grows somewhat

larger.

1% in. (4.4 cm)

Minimum temperature: 0°F (-18°C) Light: full sun The general characteristics are the same as Phyllostachys aurea, but the culms have a yellow sulcus. The compressed lower internodes on some of the culms, combined with the yellow sulcus that alternates from side to side along the internodes, offer a pleasing display of color and texture.

Phyllostachys aurea f. holochrysa Maximum

height: 27 ft. (8 m)

Maximum

diameter:

Minimum

temperature: 0°F (-18°C)

1/4 in. (4.4 cm)

Light: full sun This form of golden bamboo actually reflects the species’s common

Phyllostachys aurea {. takemurai lacks the compressed internodes of the type form, and

name. The new culms

are pale green, turning progressively to a golden yellow or orange-gold. It is otherwise similar to the type form.

Phyllostachys aurea ‘Koi’ Maximum

height: 27 ft. (8 m)

Maximum

diameter:

Minimum

temperature:

17/4 in. (4.4 cm) 0°F (—18°C)

Light: full sun The inverse of Phyllostachys aurea {. flavescensinversa, the culms of P. aurea ‘Koi’ turn yellow, but the sulcus remains green. The leaves may have an occasional white stripe. Richard Haubrich discovered the bamboo at a booth at the county fair in San Diego, California. He named

it ‘Koi’, a Latinization of the first name of the plant’s owner, Ko Tsushima. The general characteristics are the same as P. aurea.

Phyllostachys aurea f. takemurai Maximum

height:

32 ft. (9.6 m)

Maximum

diameter: 2

in. (6.3 cm)

Minimum temperature: 0°F (—18°C) Light: full sun

Phyllostachys aureosulcata

Common synonym: Phyllostachys nevinni Common name: yellow groove bamboo Maximum height: 45 ft. (14 m) Maximum diameter: 2% in. (6 cm) Minimum

temperature:

—15°F

(—26°C)

Light: full sun Known as yellow groove bamboo, Phyllostachys aureosulcata is an excellent, cold hardy ornamental with dark green culms and a yellow sulcus. It is further distinguished by the sharp bending and zigzagging of the lower part of some of the culms. As they are growing, they look at times as if someone had bent or broken them—when I first saw this, I thought that someone had vandalized my precious new shoots. The culms regain their vertical direction, however, and the grove has an upright habit. The early midseason shoots are attractive and free of bitterness even when raw. The new culms have a matt finish and are rough to the touch. The crooked lower culms enhance the ornamental appeal, though the’bends limit the usefulness of the culm wood, which is, in any case, not of the highest quality. Phyllostachys aureosulcata is one of the more widely planted ornamental bamboos in China and the United States. First introduced into America in 1907 from Zhejiang Province, it

was widely distributed by the USDA in the 1920s, when it was identified as P. nevinni. The species establishes rapidly and is an excellent choice for climates with cold winters, such as in the American Northeast and Midwest—and in Beijing, where Chinese studies have recommended it as a hardy, winter survivor. Although it will not achieve its largest size in cold climates, P. aureosulcata is nevertheless an excellent ornamental and screen for cold climate conditions, It is a vigorous grower and runner

in warm climates with favorable conditions.

B17

Chapter 9: Bamboo Genera, Species,

and Cultivars

Phyllostachys aureosulcata f. alata Common

synonym: Phyllostachys aureosulcata

Phyllostachys aureosulcata f. spectabilis Maximum

height: 32 ft. (9.6 m)

Maximum height: 48 ft. (15 m) Maximum diameter: 2 in. (6 cm)

Maximum

diameter:

Minimum

temperature: —15°F

Minimum

Light: full sun A choice ornamental, Phyllostachys aureosulcata {. spectabilis is similar to the principal form in general characteristics, but the coloring is much different. The culms are yellow with a green sulcus. The culms and branches often take on rose-red to purple-red tints with exposure to the sun. Some leaves have light, variegated striping, though this is not a prominent feature. During shooting, and as the new culm elongates, the attractive culm leaves are further set off by the emerging yellow internodes.

f. pekinensis

temperature: —15°F (-26°C)

Light: full sun The general characteristics are the same as

Phyllostachys aureosulcata, except the sulcus is green, not yellow. Under similar growing conditions, it reportedly grows larger.

Phyllostachys aureosulcata f.

aureocaulis

Maximum height: 32 ft. (9.6 m) Maximum diameter: 1° in. (4.4 cm)

Minimum

temperature: —15°F (-26°C)

Light: full sun Phyllostachys aureosulcata {. aureocaulis is a very attractive ornamental. The culms are entirely yellow, except for occasional green striping on the lowest internodes. Like in the other variants of this species (as well as many other bamboos with yellow culms), the culms and branches often take on rose-red to purple-red tints with exposure to the sun. This characteristic seems to be most evident on young culms

and when there is nighttime cooling. It is otherwise similar to the type form.

Phyllostachys aureosulcata ‘Harbin’

1% in. (4.4 cm) (-26°C)

Phyllostachys bambusoides Common

synonyms: Phyllostachys quilioi, P. reti-

culata

Common names: Japanese timber bamboo, madake Maximum height: 72 ft. (22 m) Maximum

diameter: 6 in. (15 cm)

Minimum

temperature:

5°F (—15°C)

Light: full sun Phyllostachys bambusoides originated in China, but has long been cultivated in Japan, where it

is the most widely grown timber bamboo. Introduced into Europe in 1866 by the French

Maximum

height: 32 ft. (9.6 m)

admiral Du Quilio, the species was once named

Maximum

diameter:

P. quilioi. It first came to America around 1890. One of the latest shooting species of the genus, Phyllostachys bambusoides sometimes does not initiate shoots until early summer. The young culms are glossy green, not pruinose. Young plants have long, prominent lower branches. Mature plants are free of branches on the lower nodes. An emerging culm in a mature grove has been recorded at

1/4 in. (4.4 cm)

Minimum temperature: —15°F (—26°C) Light: full sun Another attractive variation of Phyllostachys

aureosulcata, ‘Harbin’ has yellow culms with multiple, thin, green stripes and ribbing that run the length of the internodes. In 1990, New England bamboo

nurseryman

Chris DeRosa

discovered it growing at the USDA Plant Quarantine Station in Glendale, Maryland. It was subsequently introduced into Europe in 1991.

a growth

rate of 47.6 in. (121

cm)

ina

single

day (Austin et al. 1970). Individual culms are

among the longest lived, producing new leafy

ea Phyllostachys aureosulcata f. spectabilis, showing the characteristic bending of the lower portions

of some culms. Author's garden

314

Chapter 9: Bamboo Genera, Species, and Cultivars twigs each year culms of many for only

for two decades or more. The other

woody

bamboos

may live

5 to 10 years.

Phyllostachys bambusoides is one of the true giant tree grasses. bamboos,

only

Of the temperate timber

P. heterocycla f. pubescens is po-

tentially larger. It must be said, however, that P. bambusoides seldom achieves its maximum stated diameter.

In the long-established forests

of Japan, the culms reportedly average closer

to 3’ in. (9 cm) in diameter (Haubrich 1996). In the United States, even in established groves, the diameter rarely exceeds 3 in. (7.5 cm).

In Japan, P. bambusoides and P. heterocycla

sively, and many plants died or were severely weakened. A decade or so before I became interested in bamboo,

a beautiful plant emerged

in my

greenbelt area. It had apparently migrated from my neighbor's yard. I first noticed it in the winter, after the foliage from the deciduous trees had fallen away, and the first snowfall graced the bamboo’s delicate leaves. I think I dimly realized at the time that it was a bamboo, but I thought little else about it. As I was clearing back some of the greenbelt growth the following year, Isaved a culm. After that, no more bamboo appeared, and I wondered why.

f. pubescens are primarily distributed in the warmer regions. Japan’s third major timber bamboo,

P. nigra var. henonis,

is generally

dis-

tributed in cooler or more mountainous areas.

The culm wood of Phyllostachys bambusoides is ideal for construction—thick, straight, and strong—among

the best of the Phyllostachys,

and far superior to P. vivax, which it somewhat resembles.

Relative

to P. vivax,

the culms of P.

bambusoides are straighter and the branches

more upright and are produced at lower culm nodes. Phyllostachys bambusoides is one of the

latest shooting of the genus; P. vivax shoots relatively early. Unlike P. vivax, the shoots of P. bam-

busoides are somewhat bitter, though they are acceptable for the table after parboiling. Phyllostachys bambusoides establishes and attains size much

more slowly

than P. vivax, and it is not as

cold hardy. Because P. bambusoides takes longer

to establish, it is not ideal when a tall screen is quickly needed, but rewards those who can afford the extra wait. From a landscaping perspective, P. bambusoides and P. vivax are similar

in appearance.

From a commercial or utiliza-

tion perspective, they are quite different. Reportedly,

Phyllostachys bambusoides

flowers

every 120 years, but this must be regarded as somewhat speculative. After the Second World War, approximately three-fourths of the P bambusoides in Japan flowered and died back. In America,

in the 1970s, it flowered exten-

Phyllostachys bambusoides. The culm leaf is beginning to drop away as the new branches emerge. Author's garden.

5 5

fo)

gel

8